diff --git a/ts/ConversationController.ts b/ts/ConversationController.ts
index 4c65b0661c..887e0d696f 100644
--- a/ts/ConversationController.ts
+++ b/ts/ConversationController.ts
@@ -279,7 +279,12 @@ export class ConversationController {
   getOurConversationId(): string | undefined {
     const e164 = window.textsecure.storage.user.getNumber();
     const uuid = window.textsecure.storage.user.getUuid()?.toString();
-    return this.ensureContactIds({ e164, uuid, highTrust: true });
+    return this.ensureContactIds({
+      e164,
+      uuid,
+      highTrust: true,
+      reason: 'getOurConversationId',
+    });
   }
 
   getOurConversationIdOrThrow(): string {
@@ -325,11 +330,20 @@ export class ConversationController {
     e164,
     uuid,
     highTrust,
-  }: {
-    e164?: string | null;
-    uuid?: string | null;
-    highTrust?: boolean;
-  }): string | undefined {
+    reason,
+  }:
+    | {
+        e164?: string | null;
+        uuid?: string | null;
+        highTrust?: false;
+        reason?: void;
+      }
+    | {
+        e164?: string | null;
+        uuid?: string | null;
+        highTrust: true;
+        reason: string;
+      }): string | undefined {
     // Check for at least one parameter being provided. This is necessary
     // because this path can be called on startup to resolve our own ID before
     // our phone number or UUID are known. The existing behavior in these
@@ -346,7 +360,10 @@ export class ConversationController {
 
     // 1. Handle no match at all
     if (!convoE164 && !convoUuid) {
-      log.info('ensureContactIds: Creating new contact, no matches found');
+      log.info(
+        'ensureContactIds: Creating new contact, no matches found',
+        highTrust ? reason : 'no reason'
+      );
       const newConvo = this.getOrCreate(identifier, 'private');
       if (highTrust && e164) {
         newConvo.updateE164(e164);
@@ -375,7 +392,10 @@ export class ConversationController {
       // Fill in the UUID for an e164-only contact
       if (normalizedUuid && !convoE164.get('uuid')) {
         if (highTrust) {
-          log.info('ensureContactIds: Adding UUID to e164-only match');
+          log.info(
+            `ensureContactIds: Adding UUID (${uuid}) to e164-only match ` +
+              `(${e164}), reason: ${reason}`
+          );
           convoE164.updateUuid(normalizedUuid);
           updateConversation(convoE164.attributes);
         }
@@ -389,7 +409,10 @@ export class ConversationController {
       const newConvo = this.getOrCreate(normalizedUuid, 'private');
 
       if (highTrust) {
-        log.info('ensureContactIds: Moving e164 from old contact to new');
+        log.info(
+          `ensureContactIds: Moving e164 (${e164}) from old contact ` +
+            `(${convoE164.get('uuid')}) to new (${uuid}), reason: ${reason}`
+        );
 
         // Remove the e164 from the old contact...
         convoE164.set({ e164: undefined });
@@ -406,7 +429,10 @@ export class ConversationController {
     }
     if (!convoE164 && convoUuid) {
       if (e164 && highTrust) {
-        log.info('ensureContactIds: Adding e164 to UUID-only match');
+        log.info(
+          `ensureContactIds: Adding e164 (${e164}) to UUID-only match ` +
+            `(${uuid}), reason: ${reason}`
+        );
         convoUuid.updateE164(e164);
         updateConversation(convoUuid.attributes);
       }
@@ -429,7 +455,9 @@ export class ConversationController {
       // Conflict: If e164 match already has a UUID, we remove its e164.
       if (convoE164.get('uuid') && convoE164.get('uuid') !== normalizedUuid) {
         log.info(
-          'ensureContactIds: e164 match had different UUID than incoming pair, removing its e164.'
+          `ensureContactIds: e164 match (${e164}) had different ` +
+            `UUID(${convoE164.get('uuid')}) than incoming pair (${uuid}), ` +
+            `removing its e164, reason: ${reason}`
         );
 
         // Remove the e164 from the old contact...
diff --git a/ts/background.ts b/ts/background.ts
index a9f342b16c..66deca8cde 100644
--- a/ts/background.ts
+++ b/ts/background.ts
@@ -2467,6 +2467,7 @@ export async function startApp(): Promise<void> {
       e164: sender,
       uuid: senderUuid,
       highTrust: true,
+      reason: `onTyping(${typing.timestamp})`,
     });
 
     // We multiplex between GV1/GV2 groups here, but we don't kick off migrations
@@ -2607,6 +2608,7 @@ export async function startApp(): Promise<void> {
         e164: details.number,
         uuid: details.uuid,
         highTrust: true,
+        reason: 'onContactReceived',
       });
       // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
       const conversation = window.ConversationController.get(detailsId)!;
@@ -2835,6 +2837,7 @@ export async function startApp(): Promise<void> {
         e164: envelope.source,
         uuid: envelope.sourceUuid,
         highTrust: true,
+        reason: `onEnvelopeReceived(${envelope.timestamp})`,
       });
     }
   }
@@ -2970,6 +2973,7 @@ export async function startApp(): Promise<void> {
       e164: data.source,
       uuid: data.sourceUuid,
       highTrust: true,
+      reason: 'onProfileKeyUpdate',
     });
     const conversation = window.ConversationController.get(conversationId);
 
@@ -3055,6 +3059,7 @@ export async function startApp(): Promise<void> {
               uuid: destinationUuid,
               e164: destination,
               highTrust: true,
+              reason: `unidentifiedStatus(${timestamp})`,
             }
           );
           if (!conversationId || conversationId === ourId) {
@@ -3187,6 +3192,7 @@ export async function startApp(): Promise<void> {
         e164: source,
         uuid: sourceUuid,
         highTrust: true,
+        reason: `getMessageDescriptor(${message.timestamp}): group v1`,
       });
 
       const conversationId = window.ConversationController.ensureGroup(id, {
@@ -3203,6 +3209,7 @@ export async function startApp(): Promise<void> {
       e164: destination,
       uuid: destinationUuid,
       highTrust: true,
+      reason: `getMessageDescriptor(${message.timestamp}): private`,
     });
     if (!id) {
       confirm();
@@ -3609,6 +3616,7 @@ export async function startApp(): Promise<void> {
         e164: source,
         uuid: sourceUuid,
         highTrust: true,
+        reason: `onReadOrViewReceipt(${envelopeTimestamp})`,
       }
     );
     log.info(
@@ -3775,6 +3783,7 @@ export async function startApp(): Promise<void> {
       e164,
       uuid,
       highTrust: true,
+      reason: 'onVerified',
     });
     // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
     const contact = window.ConversationController.get(verifiedId)!;
@@ -3805,6 +3814,7 @@ export async function startApp(): Promise<void> {
         e164: source,
         uuid: sourceUuid,
         highTrust: true,
+        reason: `onDeliveryReceipt(${envelopeTimestamp})`,
       }
     );
 
diff --git a/ts/models/conversations.ts b/ts/models/conversations.ts
index a9b29c97bb..8de2381735 100644
--- a/ts/models/conversations.ts
+++ b/ts/models/conversations.ts
@@ -1870,7 +1870,7 @@ export class ConversationModel extends window.Backbone
       this.set('e164', e164);
 
       if (oldValue) {
-        this.addChangeNumberNotification();
+        this.addChangeNumberNotification(oldValue, e164);
       }
 
       window.Signal.Data.updateConversation(this.attributes);
@@ -3220,7 +3220,10 @@ export class ConversationModel extends window.Backbone
     this.set('pendingUniversalTimer', undefined);
   }
 
-  async addChangeNumberNotification(): Promise<void> {
+  async addChangeNumberNotification(
+    oldValue: string,
+    newValue: string
+  ): Promise<void> {
     const sourceUuid = this.getCheckedUuid(
       'Change number notification without uuid'
     );
@@ -3236,7 +3239,7 @@ export class ConversationModel extends window.Backbone
 
     log.info(
       `Conversation ${this.idForLogging()}: adding change number ` +
-        `notification for ${sourceUuid.toString()}`
+        `notification for ${sourceUuid.toString()} from ${oldValue} to ${newValue}`
     );
 
     const convos = [
diff --git a/ts/models/messages.ts b/ts/models/messages.ts
index bc8a960cda..a3a54ef599 100644
--- a/ts/models/messages.ts
+++ b/ts/models/messages.ts
@@ -2247,6 +2247,7 @@ export class MessageModel extends window.Backbone.Model<MessageAttributesType> {
                   uuid: destinationUuid,
                   e164: destination,
                   highTrust: true,
+                  reason: `handleDataMessage(${initialMessage.timestamp})`,
                 });
               if (!destinationConversationId) {
                 return;
diff --git a/ts/services/storageRecordOps.ts b/ts/services/storageRecordOps.ts
index 84a1d1d40d..be640b9db0 100644
--- a/ts/services/storageRecordOps.ts
+++ b/ts/services/storageRecordOps.ts
@@ -770,6 +770,7 @@ export async function mergeContactRecord(
     e164,
     uuid,
     highTrust: true,
+    reason: 'mergeContactRecord',
   });
 
   if (!id) {
diff --git a/ts/textsecure/AccountManager.ts b/ts/textsecure/AccountManager.ts
index 72f2dc56de..cc1b85570b 100644
--- a/ts/textsecure/AccountManager.ts
+++ b/ts/textsecure/AccountManager.ts
@@ -604,6 +604,7 @@ export default class AccountManager extends EventTarget {
       e164: number,
       uuid: ourUuid,
       highTrust: true,
+      reason: 'createAccount',
     });
 
     if (!conversationId) {
diff --git a/ts/updateConversationsWithUuidLookup.ts b/ts/updateConversationsWithUuidLookup.ts
index afd52d9cf0..0e8b0bc805 100644
--- a/ts/updateConversationsWithUuidLookup.ts
+++ b/ts/updateConversationsWithUuidLookup.ts
@@ -43,6 +43,7 @@ export async function updateConversationsWithUuidLookup({
         e164,
         uuid: uuidFromServer,
         highTrust: true,
+        reason: 'updateConversationsWithUuidLookup',
       });
       const maybeFinalConversation =
         conversationController.get(finalConversationId);