diff --git a/api/src/chat/services/block.service.spec.ts b/api/src/chat/services/block.service.spec.ts
index cc94f34e..b945cacc 100644
--- a/api/src/chat/services/block.service.spec.ts
+++ b/api/src/chat/services/block.service.spec.ts
@@ -16,7 +16,7 @@ import {
   subscriberWithLabels,
   subscriberWithoutLabels,
 } from '@/channel/lib/__test__/subscriber.mock';
-import { PayloadType } from '@/chat/schemas/types/button';
+import { ButtonType, PayloadType } from '@/chat/schemas/types/button';
 import { ContentTypeRepository } from '@/cms/repositories/content-type.repository';
 import { ContentRepository } from '@/cms/repositories/content.repository';
 import { ContentTypeModel } from '@/cms/schemas/content-type.schema';
@@ -84,13 +84,43 @@ import { BlockRepository } from '../repositories/block.repository';
 import { Block, BlockFull, BlockModel } from '../schemas/block.schema';
 import { Category, CategoryModel } from '../schemas/category.schema';
 import { LabelModel } from '../schemas/label.schema';
+import { Subscriber } from '../schemas/subscriber.schema';
 import { FileType } from '../schemas/types/attachment';
-import { StdOutgoingListMessage } from '../schemas/types/message';
+import { Context } from '../schemas/types/context';
+import {
+  OutgoingMessageFormat,
+  StdOutgoingListMessage,
+} from '../schemas/types/message';
+import { QuickReplyType } from '../schemas/types/quick-reply';
 
 import { CategoryRepository } from './../repositories/category.repository';
 import { BlockService } from './block.service';
 import { CategoryService } from './category.service';
 
+function makeMockBlock(overrides: Partial<Block>): Block {
+  return {
+    id: 'default',
+    message: [],
+    trigger_labels: [],
+    assign_labels: [],
+    nextBlocks: [],
+    attachedBlock: null,
+    category: null,
+    name: '',
+    patterns: [],
+    outcomes: [],
+    trigger_channels: [],
+    options: {},
+    starts_conversation: false,
+    capture_vars: [],
+    position: { x: 0, y: 0 },
+    builtin: false,
+    createdAt: new Date(),
+    updatedAt: new Date(),
+    ...overrides,
+  };
+}
+
 describe('BlockService', () => {
   let blockRepository: BlockRepository;
   let categoryRepository: CategoryRepository;
@@ -315,7 +345,7 @@ describe('BlockService', () => {
   });
 
   describe('matchNLP', () => {
-    it('should return undefined for match nlp against a block with no patterns', () => {
+    it('should return an empty array for a block with no NLP patterns', () => {
       const result = blockService.getMatchingNluPatterns(
         mockNlpGreetingFullNameEntities,
         blockEmpty,
@@ -323,7 +353,7 @@ describe('BlockService', () => {
       expect(result).toEqual([]);
     });
 
-    it('should return undefined for match nlp when no nlp entities are provided', () => {
+    it('should return an empty array when no NLP entities are provided', () => {
       const result = blockService.getMatchingNluPatterns(
         { entities: [] },
         blockGetStarted,
@@ -630,6 +660,374 @@ describe('BlockService', () => {
   });
 
   describe('processMessage', () => {
+    // generic inputs we re-use
+    const ctx: Context = {
+      vars: {
+        phone: '+1123456789',
+      },
+      user_location: {
+        address: undefined,
+        lat: 0,
+        lon: 0,
+      },
+      user: { id: 'user-id', first_name: 'Jhon', last_name: 'Doe' } as any,
+      skip: {},
+      attempt: 0,
+    }; // Context
+    const subCtx: Subscriber['context'] = {
+      vars: {
+        color: 'green',
+      },
+    }; // SubscriberContext
+    const conversationId = 'conv-id';
+
+    it('should return a text envelope when the block is a text block', async () => {
+      const block = makeMockBlock({
+        message: [
+          'Hello {{context.user.first_name}}, your phone is {{context.vars.phone}} and your favorite color is {{context.vars.color}}',
+        ],
+      });
+
+      const env = await blockService.processMessage(
+        block,
+        ctx,
+        subCtx,
+        false,
+        conversationId,
+      );
+
+      expect(env).toEqual({
+        format: OutgoingMessageFormat.text,
+        message: {
+          text: 'Hello Jhon, your phone is +1123456789 and your favorite color is green',
+        },
+      });
+    });
+
+    it('should return a text envelope when the block is a text block (local fallback)', async () => {
+      const block = makeMockBlock({
+        message: ['Hello world!'],
+        options: {
+          fallback: {
+            active: true,
+            max_attempts: 1,
+            message: ['Local fallback message ...'],
+          },
+        },
+      });
+
+      const env = await blockService.processMessage(
+        block,
+        ctx,
+        subCtx,
+        true,
+        conversationId,
+      );
+
+      expect(env).toEqual({
+        format: OutgoingMessageFormat.text,
+        message: {
+          text: 'Local fallback message ...',
+        },
+      });
+    });
+
+    it('should return a quick replies envelope when the block message has quickReplies', async () => {
+      const block = makeMockBlock({
+        message: {
+          text: '{{context.user.first_name}}, is this your phone number? {{context.vars.phone}}',
+          quickReplies: [
+            { content_type: QuickReplyType.text, title: 'Yes', payload: 'YES' },
+            { content_type: QuickReplyType.text, title: 'No', payload: 'NO' },
+          ],
+        },
+      });
+
+      const env = await blockService.processMessage(
+        block,
+        ctx,
+        subCtx,
+        false,
+        conversationId,
+      );
+
+      expect(env).toEqual({
+        format: OutgoingMessageFormat.quickReplies,
+        message: {
+          text: 'Jhon, is this your phone number? +1123456789',
+          quickReplies: [
+            { content_type: QuickReplyType.text, title: 'Yes', payload: 'YES' },
+            { content_type: QuickReplyType.text, title: 'No', payload: 'NO' },
+          ],
+        },
+      });
+    });
+
+    it('should return a quick replies envelope when the block message has quickReplies (local fallback)', async () => {
+      const block = makeMockBlock({
+        message: {
+          text: '{{context.user.first_name}}, are you there?',
+          quickReplies: [
+            { content_type: QuickReplyType.text, title: 'Yes', payload: 'YES' },
+            { content_type: QuickReplyType.text, title: 'No', payload: 'NO' },
+          ],
+        },
+        options: {
+          fallback: {
+            active: true,
+            max_attempts: 1,
+            message: ['Local fallback message ...'],
+          },
+        },
+      });
+
+      const env = await blockService.processMessage(
+        block,
+        ctx,
+        subCtx,
+        true,
+        conversationId,
+      );
+
+      expect(env).toEqual({
+        format: OutgoingMessageFormat.quickReplies,
+        message: {
+          text: 'Local fallback message ...',
+          quickReplies: [
+            { content_type: QuickReplyType.text, title: 'Yes', payload: 'YES' },
+            { content_type: QuickReplyType.text, title: 'No', payload: 'NO' },
+          ],
+        },
+      });
+    });
+
+    it('should return a buttons envelope when the block message has buttons', async () => {
+      const block = makeMockBlock({
+        message: {
+          text: '{{context.user.first_name}} {{context.user.last_name}}, what color do you like? {{context.vars.color}}?',
+          buttons: [
+            { type: ButtonType.postback, title: 'Red', payload: 'RED' },
+            { type: ButtonType.postback, title: 'Green', payload: 'GREEN' },
+          ],
+        },
+      });
+
+      const env = await blockService.processMessage(
+        block,
+        ctx,
+        subCtx,
+        false,
+        conversationId,
+      );
+
+      expect(env).toEqual({
+        format: OutgoingMessageFormat.buttons,
+        message: {
+          text: 'Jhon Doe, what color do you like? green?',
+          buttons: [
+            {
+              type: ButtonType.postback,
+              title: 'Red',
+              payload: 'RED',
+            },
+            {
+              type: ButtonType.postback,
+              title: 'Green',
+              payload: 'GREEN',
+            },
+          ],
+        },
+      });
+    });
+
+    it('should return a buttons envelope when the block message has buttons (local fallback)', async () => {
+      const block = makeMockBlock({
+        message: {
+          text: '{{context.user.first_name}} {{context.user.last_name}}, what color do you like? {{context.vars.color}}?',
+          buttons: [
+            { type: ButtonType.postback, title: 'Red', payload: 'RED' },
+            { type: ButtonType.postback, title: 'Green', payload: 'GREEN' },
+          ],
+        },
+        options: {
+          fallback: {
+            active: true,
+            max_attempts: 1,
+            message: ['Local fallback message ...'],
+          },
+        },
+      });
+
+      const env = await blockService.processMessage(
+        block,
+        ctx,
+        subCtx,
+        true,
+        conversationId,
+      );
+
+      expect(env).toEqual({
+        format: OutgoingMessageFormat.buttons,
+        message: {
+          text: 'Local fallback message ...',
+          buttons: [
+            {
+              type: ButtonType.postback,
+              title: 'Red',
+              payload: 'RED',
+            },
+            {
+              type: ButtonType.postback,
+              title: 'Green',
+              payload: 'GREEN',
+            },
+          ],
+        },
+      });
+    });
+
+    it('should return an attachment envelope when payload has an id', async () => {
+      const block = makeMockBlock({
+        message: {
+          attachment: {
+            type: FileType.image,
+            payload: { id: 'ABC123' },
+          },
+        },
+      });
+
+      const env = await blockService.processMessage(
+        block,
+        ctx,
+        subCtx,
+        false,
+        conversationId,
+      );
+
+      expect(env).toEqual({
+        format: OutgoingMessageFormat.attachment,
+        message: {
+          attachment: {
+            type: 'image',
+            payload: { id: 'ABC123' },
+          },
+        },
+      });
+    });
+
+    it('should return an attachment envelope when payload has an id (local fallback)', async () => {
+      const block = makeMockBlock({
+        message: {
+          attachment: {
+            type: FileType.image,
+            payload: { id: 'ABC123' },
+          },
+          quickReplies: [],
+        },
+        options: {
+          fallback: {
+            active: true,
+            max_attempts: 1,
+            message: ['Local fallback ...'],
+          },
+        },
+      });
+
+      const env = await blockService.processMessage(
+        block,
+        ctx,
+        subCtx,
+        true,
+        conversationId,
+      );
+
+      expect(env).toEqual({
+        format: OutgoingMessageFormat.text,
+        message: {
+          text: 'Local fallback ...',
+        },
+      });
+    });
+
+    it('should keep quickReplies when present in an attachment block', async () => {
+      const block = makeMockBlock({
+        message: {
+          attachment: {
+            type: FileType.video,
+            payload: { id: 'VID42' },
+          },
+          quickReplies: [
+            {
+              content_type: QuickReplyType.text,
+              title: 'Replay',
+              payload: 'REPLAY',
+            },
+            {
+              content_type: QuickReplyType.text,
+              title: 'Next',
+              payload: 'NEXT',
+            },
+          ],
+        },
+      });
+
+      const env = await blockService.processMessage(
+        block,
+        ctx,
+        subCtx,
+        false,
+        conversationId,
+      );
+      expect(env).toEqual({
+        format: OutgoingMessageFormat.attachment,
+        message: {
+          attachment: {
+            type: FileType.video,
+            payload: {
+              id: 'VID42',
+            },
+          },
+          quickReplies: [
+            {
+              content_type: QuickReplyType.text,
+              title: 'Replay',
+              payload: 'REPLAY',
+            },
+            {
+              content_type: QuickReplyType.text,
+              title: 'Next',
+              payload: 'NEXT',
+            },
+          ],
+        },
+      });
+    });
+
+    it('should throw when attachment payload misses an id (remote URLs deprecated)', async () => {
+      const spyCheckDeprecated = jest
+        .spyOn(blockService as any, 'checkDeprecatedAttachmentUrl')
+        .mockImplementation(() => {});
+
+      const block = makeMockBlock({
+        message: {
+          attachment: {
+            type: FileType.image,
+            payload: { url: 'https://example.com/old-way.png' }, // no "id"
+          },
+        },
+      });
+
+      await expect(
+        blockService.processMessage(block, ctx, subCtx, false, conversationId),
+      ).rejects.toThrow(
+        'Remote attachments in blocks are no longer supported!',
+      );
+
+      expect(spyCheckDeprecated).toHaveBeenCalledTimes(1);
+
+      spyCheckDeprecated.mockRestore();
+    });
+
     it('should process list message (with limit = 2 and skip = 0)', async () => {
       const contentType = (await contentTypeService.findOne({
         name: 'Product',
diff --git a/api/src/chat/services/block.service.ts b/api/src/chat/services/block.service.ts
index 569c75cc..47bc9cc1 100644
--- a/api/src/chat/services/block.service.ts
+++ b/api/src/chat/services/block.service.ts
@@ -36,13 +36,12 @@ import { Label } from '../schemas/label.schema';
 import { Subscriber } from '../schemas/subscriber.schema';
 import { Context } from '../schemas/types/context';
 import {
-  BlockMessage,
   OutgoingMessageFormat,
   StdOutgoingEnvelope,
   StdOutgoingSystemEnvelope,
 } from '../schemas/types/message';
 import { NlpPattern, PayloadPattern } from '../schemas/types/pattern';
-import { Payload, StdQuickReply } from '../schemas/types/quick-reply';
+import { Payload } from '../schemas/types/quick-reply';
 import { SubscriberContext } from '../schemas/types/subscriberContext';
 
 @Injectable()
@@ -599,7 +598,7 @@ export class BlockService extends BaseService<
    *
    * @param block - The block holding the message to process
    * @param context - Context object
-   * @param fallback - Whenever to process main message or local fallback message
+   * @param isLocalFallback - Whenever to process main message or local fallback message
    * @param conversationId - The conversation ID
    *
    * @returns - Envelope containing message format and content following {format, message} object structure
@@ -608,118 +607,78 @@ export class BlockService extends BaseService<
     block: Block | BlockFull,
     context: Context,
     subscriberContext: SubscriberContext,
-    fallback = false,
+    isLocalFallback = false,
     conversationId?: string,
   ): Promise<StdOutgoingEnvelope> {
     const settings = await this.settingService.getSettings();
-    const blockMessage: BlockMessage =
-      fallback && block.options?.fallback
-        ? [...block.options.fallback.message]
-        : Array.isArray(block.message)
-          ? [...block.message]
-          : { ...block.message };
+    const envelopeFactory = new EnvelopeFactory(
+      {
+        ...context,
+        vars: {
+          ...context.vars,
+          ...subscriberContext.vars,
+        },
+      },
+      settings,
+      this.i18n,
+    );
+    const fallback = isLocalFallback ? block.options?.fallback : undefined;
 
-    if (Array.isArray(blockMessage)) {
+    if (Array.isArray(block.message)) {
       // Text Message
-      // Get random message from array
-      const text = this.processText(
-        getRandomElement(blockMessage),
-        context,
-        subscriberContext,
-        settings,
+      return envelopeFactory.buildTextEnvelope(
+        fallback ? fallback.message : block.message,
       );
-      const envelope: StdOutgoingEnvelope = {
-        format: OutgoingMessageFormat.text,
-        message: { text },
-      };
-      return envelope;
-    } else if (blockMessage && 'text' in blockMessage) {
+    } else if ('text' in block.message) {
       if (
-        'quickReplies' in blockMessage &&
-        Array.isArray(blockMessage.quickReplies) &&
-        blockMessage.quickReplies.length > 0
+        'quickReplies' in block.message &&
+        Array.isArray(block.message.quickReplies) &&
+        block.message.quickReplies.length > 0
       ) {
-        const envelope: StdOutgoingEnvelope = {
-          format: OutgoingMessageFormat.quickReplies,
-          message: {
-            text: this.processText(
-              blockMessage.text,
-              context,
-              subscriberContext,
-              settings,
-            ),
-            quickReplies: blockMessage.quickReplies.map((qr: StdQuickReply) => {
-              return qr.title
-                ? {
-                    ...qr,
-                    title: this.processText(
-                      qr.title,
-                      context,
-                      subscriberContext,
-                      settings,
-                    ),
-                  }
-                : qr;
-            }),
-          },
-        };
-        return envelope;
+        return envelopeFactory.buildQuickRepliesEnvelope(
+          fallback ? fallback.message : block.message.text,
+          block.message.quickReplies,
+        );
       } else if (
-        'buttons' in blockMessage &&
-        Array.isArray(blockMessage.buttons) &&
-        blockMessage.buttons.length > 0
+        'buttons' in block.message &&
+        Array.isArray(block.message.buttons) &&
+        block.message.buttons.length > 0
       ) {
-        const envelope: StdOutgoingEnvelope = {
-          format: OutgoingMessageFormat.buttons,
-          message: {
-            text: this.processText(
-              blockMessage.text,
-              context,
-              subscriberContext,
-              settings,
-            ),
-            buttons: blockMessage.buttons.map((btn) => {
-              return btn.title
-                ? {
-                    ...btn,
-                    title: this.processText(
-                      btn.title,
-                      context,
-                      subscriberContext,
-                      settings,
-                    ),
-                  }
-                : btn;
-            }),
-          },
-        };
-        return envelope;
+        return envelopeFactory.buildButtonsEnvelope(
+          fallback ? fallback.message : block.message.text,
+          block.message.buttons,
+        );
       }
-    } else if (blockMessage && 'attachment' in blockMessage) {
-      const attachmentPayload = blockMessage.attachment.payload;
+    } else if ('attachment' in block.message) {
+      const attachmentPayload = block.message.attachment.payload;
       if (!('id' in attachmentPayload)) {
         this.checkDeprecatedAttachmentUrl(block);
         throw new Error(
           'Remote attachments in blocks are no longer supported!',
         );
       }
+      const quickReplies = block.message.quickReplies
+        ? [...block.message.quickReplies]
+        : [];
 
-      const envelope: StdOutgoingEnvelope = {
-        format: OutgoingMessageFormat.attachment,
-        message: {
-          attachment: {
-            type: blockMessage.attachment.type,
-            payload: blockMessage.attachment.payload,
-          },
-          quickReplies: blockMessage.quickReplies
-            ? [...blockMessage.quickReplies]
-            : undefined,
+      if (fallback) {
+        return quickReplies.length > 0
+          ? envelopeFactory.buildQuickRepliesEnvelope(
+              fallback.message,
+              quickReplies,
+            )
+          : envelopeFactory.buildTextEnvelope(fallback.message);
+      }
+      return envelopeFactory.buildAttachmentEnvelope(
+        {
+          type: block.message.attachment.type,
+          payload: block.message.attachment.payload,
         },
-      };
-      return envelope;
+        quickReplies,
+      );
     } else if (
-      blockMessage &&
-      'elements' in blockMessage &&
+      block.message &&
+      'elements' in block.message &&
       block.options?.content
     ) {
       const contentBlockOptions = block.options.content;
@@ -734,18 +693,21 @@ export class BlockService extends BaseService<
       }
       // Populate list with content
       try {
-        const results = await this.contentService.getContent(
+        const { elements, pagination } = await this.contentService.getContent(
           contentBlockOptions,
           skip,
         );
-        const envelope: StdOutgoingEnvelope = {
-          format: contentBlockOptions.display,
-          message: {
-            ...results,
-            options: contentBlockOptions,
-          },
-        };
-        return envelope;
+
+        return fallback
+          ? envelopeFactory.buildTextEnvelope(fallback.message)
+          : envelopeFactory.buildListEnvelope(
+              contentBlockOptions.display as
+                | OutgoingMessageFormat.list
+                | OutgoingMessageFormat.carousel,
+              contentBlockOptions,
+              elements,
+              pagination,
+            );
       } catch (err) {
         this.logger.error(
           'Unable to retrieve content for list template process',
@@ -753,10 +715,14 @@ export class BlockService extends BaseService<
         );
         throw err;
       }
-    } else if (blockMessage && 'plugin' in blockMessage) {
+    } else if (block.message && 'plugin' in block.message) {
+      if (fallback) {
+        return envelopeFactory.buildTextEnvelope(fallback.message);
+      }
+
       const plugin = this.pluginService.findPlugin(
         PluginType.block,
-        blockMessage.plugin,
+        block.message.plugin,
       );
       // Process custom plugin block
       try {
@@ -769,7 +735,7 @@ export class BlockService extends BaseService<
         return envelope;
       } catch (e) {
         this.logger.error('Plugin was unable to load/process ', e);
-        throw new Error(`Unknown plugin - ${JSON.stringify(blockMessage)}`);
+        throw new Error(`Plugin Error - ${JSON.stringify(block.message)}`);
       }
     }
     throw new Error('Invalid message format.');