diff --git a/dev/src/v1/firestore_admin_client.ts b/dev/src/v1/firestore_admin_client.ts
index aedca6d4a..6dee553f7 100644
--- a/dev/src/v1/firestore_admin_client.ts
+++ b/dev/src/v1/firestore_admin_client.ts
@@ -50,6 +50,7 @@ const version = require('../../../package.json').version;
 export class FirestoreAdminClient {
   private _terminated = false;
   private _opts: ClientOptions;
+  private _providedCustomServicePath: boolean;
   private _gaxModule: typeof gax | typeof gax.fallback;
   private _gaxGrpc: gax.GrpcClient | gax.fallback.GrpcClient;
   private _protos: {};
@@ -61,6 +62,7 @@ export class FirestoreAdminClient {
     longrunning: {},
     batching: {},
   };
+  warn: (code: string, message: string, warnType?: string) => void;
   innerApiCalls: {[name: string]: Function};
   pathTemplates: {[name: string]: gax.PathTemplate};
   operationsClient: gax.OperationsClient;
@@ -105,6 +107,9 @@ export class FirestoreAdminClient {
     const staticMembers = this.constructor as typeof FirestoreAdminClient;
     const servicePath =
       opts?.servicePath || opts?.apiEndpoint || staticMembers.servicePath;
+    this._providedCustomServicePath = !!(
+      opts?.servicePath || opts?.apiEndpoint
+    );
     const port = opts?.port || staticMembers.port;
     const clientConfig = opts?.clientConfig ?? {};
     const fallback =
@@ -258,6 +263,9 @@ export class FirestoreAdminClient {
     // of calling the API is handled in `google-gax`, with this code
     // merely providing the destination and request information.
     this.innerApiCalls = {};
+
+    // Add a warn function to the client constructor so it can be easily tested.
+    this.warn = gax.warn;
   }
 
   /**
@@ -286,7 +294,8 @@ export class FirestoreAdminClient {
           )
         : // eslint-disable-next-line @typescript-eslint/no-explicit-any
           (this._protos as any).google.firestore.admin.v1.FirestoreAdmin,
-      this._opts
+      this._opts,
+      this._providedCustomServicePath
     ) as Promise<{[method: string]: Function}>;
 
     // Iterate over each of the methods that the service provides
diff --git a/dev/src/v1/firestore_client.ts b/dev/src/v1/firestore_client.ts
index 958e74688..f216b4c27 100644
--- a/dev/src/v1/firestore_client.ts
+++ b/dev/src/v1/firestore_client.ts
@@ -55,6 +55,7 @@ const version = require('../../../package.json').version;
 export class FirestoreClient {
   private _terminated = false;
   private _opts: ClientOptions;
+  private _providedCustomServicePath: boolean;
   private _gaxModule: typeof gax | typeof gax.fallback;
   private _gaxGrpc: gax.GrpcClient | gax.fallback.GrpcClient;
   private _protos: {};
@@ -66,6 +67,7 @@ export class FirestoreClient {
     longrunning: {},
     batching: {},
   };
+  warn: (code: string, message: string, warnType?: string) => void;
   innerApiCalls: {[name: string]: Function};
   firestoreStub?: Promise<{[name: string]: Function}>;
 
@@ -108,6 +110,9 @@ export class FirestoreClient {
     const staticMembers = this.constructor as typeof FirestoreClient;
     const servicePath =
       opts?.servicePath || opts?.apiEndpoint || staticMembers.servicePath;
+    this._providedCustomServicePath = !!(
+      opts?.servicePath || opts?.apiEndpoint
+    );
     const port = opts?.port || staticMembers.port;
     const clientConfig = opts?.clientConfig ?? {};
     const fallback =
@@ -205,6 +210,9 @@ export class FirestoreClient {
     // of calling the API is handled in `google-gax`, with this code
     // merely providing the destination and request information.
     this.innerApiCalls = {};
+
+    // Add a warn function to the client constructor so it can be easily tested.
+    this.warn = gax.warn;
   }
 
   /**
@@ -233,7 +241,8 @@ export class FirestoreClient {
           )
         : // eslint-disable-next-line @typescript-eslint/no-explicit-any
           (this._protos as any).google.firestore.v1.Firestore,
-      this._opts
+      this._opts,
+      this._providedCustomServicePath
     ) as Promise<{[method: string]: Function}>;
 
     // Iterate over each of the methods that the service provides
diff --git a/dev/src/v1beta1/firestore_client.ts b/dev/src/v1beta1/firestore_client.ts
index 10fbc0a3f..a64604cdd 100644
--- a/dev/src/v1beta1/firestore_client.ts
+++ b/dev/src/v1beta1/firestore_client.ts
@@ -58,6 +58,7 @@ const version = require('../../../package.json').version;
 export class FirestoreClient {
   private _terminated = false;
   private _opts: ClientOptions;
+  private _providedCustomServicePath: boolean;
   private _gaxModule: typeof gax | typeof gax.fallback;
   private _gaxGrpc: gax.GrpcClient | gax.fallback.GrpcClient;
   private _protos: {};
@@ -69,6 +70,7 @@ export class FirestoreClient {
     longrunning: {},
     batching: {},
   };
+  warn: (code: string, message: string, warnType?: string) => void;
   innerApiCalls: {[name: string]: Function};
   firestoreStub?: Promise<{[name: string]: Function}>;
 
@@ -111,6 +113,9 @@ export class FirestoreClient {
     const staticMembers = this.constructor as typeof FirestoreClient;
     const servicePath =
       opts?.servicePath || opts?.apiEndpoint || staticMembers.servicePath;
+    this._providedCustomServicePath = !!(
+      opts?.servicePath || opts?.apiEndpoint
+    );
     const port = opts?.port || staticMembers.port;
     const clientConfig = opts?.clientConfig ?? {};
     const fallback =
@@ -208,6 +213,9 @@ export class FirestoreClient {
     // of calling the API is handled in `google-gax`, with this code
     // merely providing the destination and request information.
     this.innerApiCalls = {};
+
+    // Add a warn function to the client constructor so it can be easily tested.
+    this.warn = gax.warn;
   }
 
   /**
@@ -236,7 +244,8 @@ export class FirestoreClient {
           )
         : // eslint-disable-next-line @typescript-eslint/no-explicit-any
           (this._protos as any).google.firestore.v1beta1.Firestore,
-      this._opts
+      this._opts,
+      this._providedCustomServicePath
     ) as Promise<{[method: string]: Function}>;
 
     // Iterate over each of the methods that the service provides
diff --git a/synth.metadata b/synth.metadata
index ce7e5b0e4..eda4970c3 100644
--- a/synth.metadata
+++ b/synth.metadata
@@ -4,15 +4,15 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/nodejs-firestore.git",
-        "sha": "5e384157efda51dc91eeb314a7ac53466764af3d"
+        "sha": "8d9c50381eedf6ee8043eed681d03b44262b9820"
       }
     },
     {
       "git": {
         "name": "googleapis",
         "remote": "https://github.com/googleapis/googleapis.git",
-        "sha": "076f7e9f0b258bdb54338895d7251b202e8f0de3",
-        "internalRef": "380641501"
+        "sha": "80f404215a9346259db760d80d0671f28c433453",
+        "internalRef": "385101839"
       }
     },
     {
diff --git a/types/v1/firestore_admin_client.d.ts b/types/v1/firestore_admin_client.d.ts
index 945ebe8a0..523c92ad7 100644
--- a/types/v1/firestore_admin_client.d.ts
+++ b/types/v1/firestore_admin_client.d.ts
@@ -35,12 +35,14 @@ import * as protos from '../protos/firestore_admin_v1_proto_api';
 export declare class FirestoreAdminClient {
   private _terminated;
   private _opts;
+  private _providedCustomServicePath;
   private _gaxModule;
   private _gaxGrpc;
   private _protos;
   private _defaults;
   auth: gax.GoogleAuth;
   descriptors: Descriptors;
+  warn: (code: string, message: string, warnType?: string) => void;
   innerApiCalls: {
     [name: string]: Function;
   };
diff --git a/types/v1/firestore_client.d.ts b/types/v1/firestore_client.d.ts
index fca4787e1..139527dd9 100644
--- a/types/v1/firestore_client.d.ts
+++ b/types/v1/firestore_client.d.ts
@@ -40,12 +40,14 @@ import * as protos from '../protos/firestore_v1_proto_api';
 export declare class FirestoreClient {
   private _terminated;
   private _opts;
+  private _providedCustomServicePath;
   private _gaxModule;
   private _gaxGrpc;
   private _protos;
   private _defaults;
   auth: gax.GoogleAuth;
   descriptors: Descriptors;
+  warn: (code: string, message: string, warnType?: string) => void;
   innerApiCalls: {
     [name: string]: Function;
   };
diff --git a/types/v1beta1/firestore_client.d.ts b/types/v1beta1/firestore_client.d.ts
index 2f182209a..24ea51b39 100644
--- a/types/v1beta1/firestore_client.d.ts
+++ b/types/v1beta1/firestore_client.d.ts
@@ -41,12 +41,14 @@ import * as protos from '../protos/firestore_v1beta1_proto_api';
 export declare class FirestoreClient {
   private _terminated;
   private _opts;
+  private _providedCustomServicePath;
   private _gaxModule;
   private _gaxGrpc;
   private _protos;
   private _defaults;
   auth: gax.GoogleAuth;
   descriptors: Descriptors;
+  warn: (code: string, message: string, warnType?: string) => void;
   innerApiCalls: {
     [name: string]: Function;
   };