diff --git a/protos/SignalService.proto b/protos/SignalService.proto
index 50947dbde..6ddcf056e 100644
--- a/protos/SignalService.proto
+++ b/protos/SignalService.proto
@@ -47,7 +47,7 @@ message MessageRequestResponse {
 message Content {
 
   enum ExpirationType {
-    LEGACY              = 0;
+    UNKNOWN             = 0;
     DELETE_AFTER_READ   = 1;
     DELETE_AFTER_SEND   = 2;
   }
diff --git a/ts/receiver/contentMessage.ts b/ts/receiver/contentMessage.ts
index 93570a1e8..dc9226a07 100644
--- a/ts/receiver/contentMessage.ts
+++ b/ts/receiver/contentMessage.ts
@@ -418,7 +418,7 @@ export async function innerHandleSwarmContentMessage(
 
       const isLegacy = Boolean(
         (!content.expirationType && !content.expirationTimer) ||
-          content.expirationType === SignalService.Content.ExpirationType.LEGACY
+          content.expirationType === SignalService.Content.ExpirationType.UNKNOWN
       );
       const isLegacyMessage = Boolean(
         isLegacy && dataMessage.expireTimer && dataMessage.expireTimer > -1
diff --git a/ts/session/messages/outgoing/ExpirableMessage.ts b/ts/session/messages/outgoing/ExpirableMessage.ts
index 5325095f5..ce11e1aa2 100644
--- a/ts/session/messages/outgoing/ExpirableMessage.ts
+++ b/ts/session/messages/outgoing/ExpirableMessage.ts
@@ -31,7 +31,7 @@ export class ExpirableMessage extends ContentMessage {
           : this.expirationType === 'deleteAfterRead'
           ? SignalService.Content.ExpirationType.DELETE_AFTER_READ
           : this.expirationType === 'legacy'
-          ? SignalService.Content.ExpirationType.LEGACY
+          ? SignalService.Content.ExpirationType.UNKNOWN
           : undefined,
       expirationTimer: this.expireTimer && this.expireTimer > -1 ? this.expireTimer : undefined,
     });
diff --git a/ts/session/messages/outgoing/controlMessage/group/ClosedGroupMessage.ts b/ts/session/messages/outgoing/controlMessage/group/ClosedGroupMessage.ts
index 2c04bff31..c20a18229 100644
--- a/ts/session/messages/outgoing/controlMessage/group/ClosedGroupMessage.ts
+++ b/ts/session/messages/outgoing/controlMessage/group/ClosedGroupMessage.ts
@@ -37,7 +37,7 @@ export abstract class ClosedGroupMessage extends ExpirableMessage {
         this.expirationType === 'deleteAfterSend'
           ? SignalService.Content.ExpirationType.DELETE_AFTER_SEND
           : !this.expirationType || this.expirationType === 'legacy'
-          ? SignalService.Content.ExpirationType.LEGACY
+          ? SignalService.Content.ExpirationType.UNKNOWN
           : undefined,
     });
   }