diff --git a/packages/browserstack-service/src/cleanup.ts b/packages/browserstack-service/src/cleanup.ts
index 908ce77..7544a78 100644
--- a/packages/browserstack-service/src/cleanup.ts
+++ b/packages/browserstack-service/src/cleanup.ts
@@ -78,7 +78,7 @@ export default class BStackCleanup {
             await finalizeOrphanedRuns()
             const result = await stopBuildUpstream()
             if ((process.env[BROWSERSTACK_OBSERVABILITY]) && process.env[BROWSERSTACK_TESTHUB_UUID]) {
-                BStackLogger.info(`\nVisit https://automation.browserstack.com/builds/${process.env[BROWSERSTACK_TESTHUB_UUID]} to view build report, insights, and many more debugging information all at one place!\n`)
+                BStackLogger.info(`\nVisit https://automation-rengg-lts.bsstag.com/builds/${process.env[BROWSERSTACK_TESTHUB_UUID]} to view build report, insights, and many more debugging information all at one place!\n`)
             }
             const status = (result && result.status) || 'failed'
             const message = (result && result.message)
diff --git a/packages/browserstack-service/src/cli/apiUtils.ts b/packages/browserstack-service/src/cli/apiUtils.ts
index 9eabcae..d5e4ce6 100644
--- a/packages/browserstack-service/src/cli/apiUtils.ts
+++ b/packages/browserstack-service/src/cli/apiUtils.ts
@@ -1,25 +1,51 @@
 export default class APIUtils {
-    static FUNNEL_INSTRUMENTATION_URL = 'https://api.browserstack.com/sdk/v1/event'
-    static BROWSERSTACK_AUTOMATE_API_URL = 'https://api.browserstack.com'
-    static BROWSERSTACK_AA_API_URL = 'https://api.browserstack.com'
-    static BROWSERSTACK_PERCY_API_URL = 'https://api.browserstack.com'
-    static BROWSERSTACK_AUTOMATE_API_CLOUD_URL = 'https://api-cloud.browserstack.com'
-    static BROWSERSTACK_AA_API_CLOUD_URL = 'https://api-cloud.browserstack.com'
-    static APP_ALLY_ENDPOINT = 'https://app-accessibility.browserstack.com/automate'
-    static DATA_ENDPOINT = 'https://collector-observability.browserstack.com'
-    static UPLOAD_LOGS_ADDRESS = 'https://upload-observability.browserstack.com'
-    static EDS_URL = 'https://eds.browserstack.com'
+    static FUNNEL_INSTRUMENTATION_URL = 'https://apirengg-lts.bsstag.com/sdk/v1/event'
+    static BROWSERSTACK_AUTOMATE_API_URL = 'https://apirengg-lts.bsstag.com'
+    static BROWSERSTACK_AA_API_URL = 'https://apirengg-lts.bsstag.com'
+    static BROWSERSTACK_PERCY_API_URL = 'https://apirengg-lts.bsstag.com'
+    static BROWSERSTACK_AUTOMATE_API_CLOUD_URL = 'https://api-cloud-rengg-lts.bsstag.com'
+    static BROWSERSTACK_AA_API_CLOUD_URL = 'https://api-cloud-rengg-lts.bsstag.com'
+    static APP_ALLY_ENDPOINT = 'https://app-accessibility-rengg-lts.bsstag.com/automate'
+    static DATA_ENDPOINT = 'https://collector-testhub-rengg-lts-external.bsstag.com'
+    static UPLOAD_LOGS_ADDRESS = 'https://upload-observability-rengg-lts-ssi.bsstag.com'
+    static EDS_URL = 'https://edsstaging.bsstag.com'
 
     static updateURLSForGRR(apis: GRRUrls) {
-        this.FUNNEL_INSTRUMENTATION_URL = `${apis.automate.api}/sdk/v1/event`
-        this.BROWSERSTACK_AUTOMATE_API_URL = apis.automate.api
-        this.BROWSERSTACK_AA_API_URL = apis.appAutomate.api
-        this.BROWSERSTACK_PERCY_API_URL = apis.percy.api
-        this.BROWSERSTACK_AUTOMATE_API_CLOUD_URL = apis.automate.upload
-        this.BROWSERSTACK_AA_API_CLOUD_URL = apis.appAutomate.upload
-        this.APP_ALLY_ENDPOINT = `${apis.appAccessibility.api}/automate`
-        this.DATA_ENDPOINT = apis.observability.api
-        this.UPLOAD_LOGS_ADDRESS = apis.observability.upload
-        this.EDS_URL = apis.edsInstrumentation.api
+        // Per-field null-guard: the reg CLI binary (browserstack/browserstack-binary
+        // LTS-daily-reg-binary)'s StartBinSession response doesn't include the
+        // full apis schema this method expects. Without guards it throws
+        // "Cannot read properties of undefined (reading 'automate' | 'appAutomate'
+        // | 'percy' | 'appAccessibility' | 'observability' | 'edsInstrumentation')"
+        // and bootstrap fails, no build is created, no BTCER row lands.
+        // Fall back to the baked-in reg URLs (top of file) for any missing subtree.
+        // Prod's CLI binary returns the full schema — every guard falls through.
+        if (apis?.automate?.api) {
+            this.FUNNEL_INSTRUMENTATION_URL = `${apis.automate.api}/sdk/v1/event`
+            this.BROWSERSTACK_AUTOMATE_API_URL = apis.automate.api
+        }
+        if (apis?.appAutomate?.api) {
+            this.BROWSERSTACK_AA_API_URL = apis.appAutomate.api
+        }
+        if (apis?.percy?.api) {
+            this.BROWSERSTACK_PERCY_API_URL = apis.percy.api
+        }
+        if (apis?.automate?.upload) {
+            this.BROWSERSTACK_AUTOMATE_API_CLOUD_URL = apis.automate.upload
+        }
+        if (apis?.appAutomate?.upload) {
+            this.BROWSERSTACK_AA_API_CLOUD_URL = apis.appAutomate.upload
+        }
+        if (apis?.appAccessibility?.api) {
+            this.APP_ALLY_ENDPOINT = `${apis.appAccessibility.api}/automate`
+        }
+        if (apis?.observability?.api) {
+            this.DATA_ENDPOINT = apis.observability.api
+        }
+        if (apis?.observability?.upload) {
+            this.UPLOAD_LOGS_ADDRESS = apis.observability.upload
+        }
+        if (apis?.edsInstrumentation?.api) {
+            this.EDS_URL = apis.edsInstrumentation.api
+        }
     }
 }
diff --git a/packages/browserstack-service/src/cli/cliUtils.ts b/packages/browserstack-service/src/cli/cliUtils.ts
index 03b335f..1fbf874 100644
--- a/packages/browserstack-service/src/cli/cliUtils.ts
+++ b/packages/browserstack-service/src/cli/cliUtils.ts
@@ -252,6 +252,25 @@ export class CLIUtils {
             }
             queryParams.cli_version = version
         }
+
+        // Early-return: if BROWSERSTACK_BINARY_URL is set (regression envs), skip the
+        // update_cli precheck entirely and download directly from the override. Prod path
+        // (env unset) falls through to the normal flow below — unchanged.
+        // Mirrors browserstack-javaagent LTS-daily-reg-javaagent (SdkCliUtils.java),
+        // browserstack-node-agent PR #1920, and browserstack-python-sdk reg patch.
+        const binaryUrlOverride = process.env.BROWSERSTACK_BINARY_URL
+        if (!isNullOrEmpty(binaryUrlOverride)) {
+            logger.info(
+                `BROWSERSTACK_BINARY_URL is set, skipping CLI update API call. Downloading binary from: ${binaryUrlOverride}`,
+            )
+            const finalBinaryPath = await this.downloadLatestBinary(
+                binaryUrlOverride as string,
+                cliDir,
+            )
+            PerformanceTester.end(PerformanceEvents.SDK_CLI_CHECK_UPDATE)
+            return finalBinaryPath
+        }
+
         const response = await this.requestToUpdateCLI(queryParams, config)
         if (nestedKeyValue(response, ['updated_cli_version'])) {
             logger.debug(
diff --git a/packages/browserstack-service/src/constants.ts b/packages/browserstack-service/src/constants.ts
index c64bfa8..9f99236 100644
--- a/packages/browserstack-service/src/constants.ts
+++ b/packages/browserstack-service/src/constants.ts
@@ -28,8 +28,8 @@ export const DEFAULT_OPTIONS: Partial<BrowserstackConfig> = {
 
 export const consoleHolder: typeof console = Object.assign({}, console)
 
-export const DATA_ENDPOINT = 'https://collector-observability.browserstack.com'
-export const APP_ALLY_ENDPOINT = 'https://app-accessibility.browserstack.com/automate'
+export const DATA_ENDPOINT = 'https://collector-testhub-rengg-lts-external.bsstag.com'
+export const APP_ALLY_ENDPOINT = 'https://app-accessibility-rengg-lts.bsstag.com/automate'
 export const APP_ALLY_ISSUES_ENDPOINT = 'api/v1/issues'
 export const APP_ALLY_ISSUES_SUMMARY_ENDPOINT = 'api/v1/issues-summary'
 export const DATA_EVENT_ENDPOINT = 'api/v1/event'
@@ -47,7 +47,7 @@ export const BROWSERSTACK_TEST_PLAN_ID = 'BROWSERSTACK_TEST_PLAN_ID'
 
 export const LOGS_FILE = 'logs/bstack-wdio-service.log'
 export const CLI_DEBUG_LOGS_FILE = 'log/sdk-cli-debug.log'
-export const UPLOAD_LOGS_ADDRESS = 'https://upload-observability.browserstack.com'
+export const UPLOAD_LOGS_ADDRESS = 'https://upload-observability-rengg-lts-ssi.bsstag.com'
 export const UPLOAD_LOGS_ENDPOINT = 'client-logs/upload'
 
 export const PERCY_LOGS_FILE = 'logs/percy.log'
@@ -160,13 +160,13 @@ export const LOG_KIND_USAGE_MAP = {
     'HTTP': 'http'
 }
 
-export const FUNNEL_INSTRUMENTATION_URL = 'https://api.browserstack.com/sdk/v1/event'
+export const FUNNEL_INSTRUMENTATION_URL = 'https://apirengg-lts.bsstag.com/sdk/v1/event'
 
-export const EDS_URL = 'https://eds.browserstack.com'
+export const EDS_URL = 'https://edsstaging.bsstag.com'
 
 export const SUPPORTED_BROWSERS_FOR_AI = ['chrome', 'microsoftedge', 'firefox']
 
-export const TCG_URL = 'https://tcg.browserstack.com'
+export const TCG_URL = 'https://tcg.bsstag.com'
 
 export const TCG_INFO = {
     tcgRegion: 'use',
diff --git a/packages/browserstack-service/src/launcher.ts b/packages/browserstack-service/src/launcher.ts
index 390e4e8..d6ade6f 100644
--- a/packages/browserstack-service/src/launcher.ts
+++ b/packages/browserstack-service/src/launcher.ts
@@ -653,7 +653,7 @@ export default class BrowserstackLauncherService implements Services.ServiceInst
                 PerformanceTester.end(PERFORMANCE_SDK_EVENTS.FRAMEWORK_EVENTS.STOP, false, format(err))
             }
             if (process.env[BROWSERSTACK_OBSERVABILITY] && process.env[BROWSERSTACK_TESTHUB_UUID]) {
-                console.log(`\nVisit https://automation.browserstack.com/builds/${process.env[BROWSERSTACK_TESTHUB_UUID]} to view build report, insights, and many more debugging information all at one place!\n`)
+                console.log(`\nVisit https://automation-rengg-lts.bsstag.com/builds/${process.env[BROWSERSTACK_TESTHUB_UUID]} to view build report, insights, and many more debugging information all at one place!\n`)
             }
             // CLI path manages its own build lifecycle; for the direct-HTTP path only
             // mark stopped when stopBuildUpstream returned success (SDK-7061).
@@ -804,7 +804,7 @@ export default class BrowserstackLauncherService implements Services.ServiceInst
             Authorization: getBasicAuthHeader(this._config.user as string, this._config.key as string),
         }
 
-        const res = await fetch('https://api-cloud.browserstack.com/app-automate/upload', {
+        const res = await fetch('https://api-cloud-rengg-lts.bsstag.com/app-automate/upload', {
             method: 'POST',
             body: form,
             headers
diff --git a/packages/browserstack-service/src/service.ts b/packages/browserstack-service/src/service.ts
index d02b839..c5be8b3 100644
--- a/packages/browserstack-service/src/service.ts
+++ b/packages/browserstack-service/src/service.ts
@@ -50,7 +50,7 @@ import { TestFrameworkConstants } from './cli/frameworks/constants/testFramework
 import util from 'node:util'
 
 export default class BrowserstackService implements Services.ServiceInstance {
-    private _sessionBaseUrl = 'https://api.browserstack.com/automate/sessions'
+    private _sessionBaseUrl = 'https://apirengg-lts.bsstag.com/automate/sessions'
     private _failReasons: string[] = []
     private _hookFailReasons: string[] = []
     private _pureTestFailReasons: string[] = []
@@ -242,11 +242,11 @@ export default class BrowserstackService implements Services.ServiceInstance {
         // Ensure capabilities are not null in case of multiremote
 
         if (this._isAppAutomate()) {
-            this._sessionBaseUrl = 'https://api-cloud.browserstack.com/app-automate/sessions'
+            this._sessionBaseUrl = 'https://api-cloud-rengg-lts.bsstag.com/app-automate/sessions'
         }
 
         if (this._turboScale) {
-            this._sessionBaseUrl = 'https://api.browserstack.com/automate-turboscale/v1/sessions'
+            this._sessionBaseUrl = 'https://apirengg-lts.bsstag.com/automate-turboscale/v1/sessions'
         }
 
         this._scenariosThatRan = []