diff --git a/ghost/core/core/server/services/members/service.js b/ghost/core/core/server/services/members/service.js
index 15f5933534..6855f29d1a 100644
--- a/ghost/core/core/server/services/members/service.js
+++ b/ghost/core/core/server/services/members/service.js
@@ -105,7 +105,7 @@ module.exports = {
         });
 
         verificationTrigger = new VerificationTrigger({
-            configThreshold: _.get(config.get('hostSettings'), 'emailVerification.importThreshold'),
+            apiTriggerThreshold: _.get(config.get('hostSettings'), 'emailVerification.importThreshold'),
             isVerified: () => config.get('hostSettings:emailVerification:verified') === true,
             isVerificationRequired: () => settingsCache.get('email_verification_required') === true,
             sendVerificationEmail: ({subject, message, amountImported}) => {
diff --git a/ghost/member-events/lib/MemberCreatedEvent.js b/ghost/member-events/lib/MemberCreatedEvent.js
index 9368b4d4a9..66b6e6320f 100644
--- a/ghost/member-events/lib/MemberCreatedEvent.js
+++ b/ghost/member-events/lib/MemberCreatedEvent.js
@@ -1,7 +1,7 @@
 /**
  * @typedef {object} MemberCreatedEventData
  * @prop {string} memberId
- * @prop {string} source
+ * @prop {'import' | 'system' | 'api' | 'admin' | 'member'} source
  * @prop {import('@tryghost/member-attribution/lib/attribution').Attribution} [attribution] Attribution
  */
 
diff --git a/ghost/member-events/lib/MemberSubscribeEvent.js b/ghost/member-events/lib/MemberSubscribeEvent.js
index efc20efa34..c17af2f309 100644
--- a/ghost/member-events/lib/MemberSubscribeEvent.js
+++ b/ghost/member-events/lib/MemberSubscribeEvent.js
@@ -1,7 +1,7 @@
 /**
  * @typedef {object} MemberSubscribeEventData
  * @prop {string} memberId
- * @prop {string} source
+ * @prop {'import' | 'system' | 'api' | 'admin' | 'member'} source
  */
 
 module.exports = class MemberSubscribeEvent {
diff --git a/ghost/members-api/lib/repositories/member.js b/ghost/members-api/lib/repositories/member.js
index ce88d496fb..f1f213d01e 100644
--- a/ghost/members-api/lib/repositories/member.js
+++ b/ghost/members-api/lib/repositories/member.js
@@ -98,6 +98,11 @@ module.exports = class MemberRepository {
         return subscription.plan && subscription.plan.nickname && subscription.plan.nickname.toLowerCase() === 'complimentary';
     }
 
+    /**
+     * Maps the framework context to members_*.source table record value
+     * @param {Object} context instance of ghost framework context object
+     * @returns {'import' | 'system' | 'api' | 'admin' | 'member'}
+     */
     _resolveContextSource(context) {
         let source;
 
diff --git a/ghost/verification-trigger/lib/verification-trigger.js b/ghost/verification-trigger/lib/verification-trigger.js
index 6e693488bc..a919ea741c 100644
--- a/ghost/verification-trigger/lib/verification-trigger.js
+++ b/ghost/verification-trigger/lib/verification-trigger.js
@@ -13,7 +13,7 @@ class VerificationTrigger {
     /**
      *
      * @param {object} deps
-     * @param {number} deps.configThreshold Threshold for triggering verification as defined in config
+     * @param {number} deps.apiTriggerThreshold Threshold for triggering verification as defined in config
      * @param {() => boolean} deps.isVerified Check Ghost config to see if we are already verified
      * @param {() => boolean} deps.isVerificationRequired Check Ghost settings to see whether verification has been requested
      * @param {(content: {subject: string, message: string, amountImported: number}) => {}} deps.sendVerificationEmail Sends an email to the escalation address to confirm that customer needs to be verified
@@ -22,7 +22,7 @@ class VerificationTrigger {
      * @param {any} deps.eventRepository For querying events
      */
     constructor({
-        configThreshold,
+        apiTriggerThreshold,
         isVerified,
         isVerificationRequired,
         sendVerificationEmail,
@@ -30,7 +30,7 @@ class VerificationTrigger {
         Settings,
         eventRepository
     }) {
-        this._configThreshold = configThreshold;
+        this._apiTriggerThreshold = apiTriggerThreshold;
         this._isVerified = isVerified;
         this._isVerificationRequired = isVerificationRequired;
         this._sendVerificationEmail = sendVerificationEmail;
@@ -44,7 +44,7 @@ class VerificationTrigger {
 
     async _handleMemberSubscribeEvent(event) {
         const source = event.data?.source;
-        const sourceThreshold = this._configThreshold;
+        const sourceThreshold = this._apiTriggerThreshold;
 
         if (source === 'api' && isFinite(sourceThreshold)) {
             const createdAt = new Date();
@@ -65,7 +65,7 @@ class VerificationTrigger {
     }
 
     async getImportThreshold() {
-        const volumeThreshold = this._configThreshold;
+        const volumeThreshold = this._apiTriggerThreshold;
         if (isFinite(volumeThreshold)) {
             const membersTotal = await this._membersStats.getTotalMembers();
             return Math.max(membersTotal, volumeThreshold);
@@ -75,7 +75,7 @@ class VerificationTrigger {
     }
 
     async testImportThreshold() {
-        if (!isFinite(this._configThreshold)) {
+        if (!isFinite(this._apiTriggerThreshold)) {
             // Infinite threshold, quick path
             return;
         }
@@ -91,7 +91,7 @@ class VerificationTrigger {
 
         // Import threshold is either the total number of members (discounting any created by imports in
         // the last 30 days) or the threshold defined in config, whichever is greater.
-        const importThreshold = Math.max(membersTotal - events.meta.pagination.total, this._configThreshold);
+        const importThreshold = Math.max(membersTotal - events.meta.pagination.total, this._apiTriggerThreshold);
         if (isFinite(importThreshold) && events.meta.pagination.total > importThreshold) {
             await this.startVerificationProcess({
                 amountImported: events.meta.pagination.total,
diff --git a/ghost/verification-trigger/test/verification-trigger.test.js b/ghost/verification-trigger/test/verification-trigger.test.js
index 45bde4bd32..f7400f55ab 100644
--- a/ghost/verification-trigger/test/verification-trigger.test.js
+++ b/ghost/verification-trigger/test/verification-trigger.test.js
@@ -9,7 +9,7 @@ const {MemberSubscribeEvent} = require('@tryghost/member-events');
 describe('Import threshold', function () {
     it('Creates a threshold based on config', async function () {
         const trigger = new VerificationTrigger({
-            configThreshold: 2,
+            apiTriggerThreshold: 2,
             membersStats: {
                 getTotalMembers: async () => 1
             }
@@ -21,7 +21,7 @@ describe('Import threshold', function () {
 
     it('Increases the import threshold to the number of members', async function () {
         const trigger = new VerificationTrigger({
-            configThreshold: 2,
+            apiTriggerThreshold: 2,
             membersStats: {
                 getTotalMembers: async () => 3
             }
@@ -34,7 +34,7 @@ describe('Import threshold', function () {
     it('Does not check members count when config threshold is infinite', async function () {
         const membersStub = sinon.stub().resolves(null);
         const trigger = new VerificationTrigger({
-            configThreshold: Infinity,
+            apiTriggerThreshold: Infinity,
             memberStats: {
                 getTotalMembers: membersStub
             }
@@ -203,7 +203,7 @@ describe('Email verification flow', function () {
         });
 
         const trigger = new VerificationTrigger({
-            configThreshold: 2,
+            apiTriggerThreshold: 2,
             Settings: {
                 edit: settingsStub
             },
@@ -246,7 +246,7 @@ describe('Email verification flow', function () {
         });
 
         const trigger = new VerificationTrigger({
-            configThreshold: Infinity,
+            apiTriggerThreshold: Infinity,
             Settings: {
                 edit: settingsStub
             },