# AdStack Watch weekly — 2026-W42

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## Deadlines in the next 45 days (4)
- **2026-10-23** · Shopify: New tax fields for return shipping fees in the GraphQL Admin API — https://shopify.dev/changelog/new-return-shipping-fee-tax-fields
- **2026-11-02** · Shopify: Global Catalog REST API stops serving traffic on November 2, 2026 — https://shopify.dev/changelog/global-catalog-rest-api-stops-serving-traffic-on-november-2-2026
- **2026-11-16** · LinkedIn Marketing API: LinkedIn Marketing API version 202511 (November 2025) sunset on November 16, 2026 — https://learn.microsoft.com/en-us/linkedin/marketing/integrations/migrations
- **2026-12-01** · Shopify: Built for Shopify requirements for Returns and exchanges apps and Subscription apps (effective December 1, 2026) — https://shopify.dev/changelog/built-for-shopify-requirements-for-returns-and-exchanges-and-subscription-apps

## New this week (10)
- Shopify: Checkout MCP and Cart MCP now support UCP buyer consent (2026-10-16) — https://shopify.dev/changelog/checkout-mcp-and-cart-mcp-now-support-ucp-buyer-consent
- Shopify: Build with confidence: Shopify AI Toolkit's security check (2026-10-15) — https://shopify.dev/changelog/build-more-secure-apps-with-shopify-s-ai-toolkit-security-check
- Google Ads: Google Ads API v26 sunset (November 2027) (2026-10-14) — https://developers.google.com/google-ads/api/docs/sunset-dates
- Google Ads: Announcing v26 of the Google Ads API (2026-10-14) — https://ads-developers.googleblog.com/2026/10/announcing-v26-of-google-ads-api.html
- Shopify: Hydrogen 2026-10 is now available (2026-10-14) — https://shopify.dev/changelog/hydrogen-2026-10-is-now-available
- Shopify: Add shopping and Shop Pay checkout to any agent with Shop MCP (2026-10-13) — https://shopify.dev/changelog/add-shopping-and-shop-pay-checkout-to-any-agent-with-shop-mcp
- Google Ads: Google Ads API Release and Sunset Schedules for 2026-2027 (2026-10-12) — https://ads-developers.googleblog.com/2026/10/google-ads-api-release-and-sunset.html
- Shopify: Cart updates that result in no changes to the cart no longer trigger carts/update webhooks (2026-10-12) — https://shopify.dev/changelog/unchanged-carts-no-longer-trigger-carts-update-webhooks
- Shopify: Detect when a POS extension screen finishes navigating (2026-10-12) — https://shopify.dev/changelog/detect-when-a-pos-extension-screen-finishes-navigating
- Shopify: Identify the published version running in a POS extension (2026-10-12) — https://shopify.dev/changelog/identify-the-published-version-running-in-a-pos-extension

## GTM price moves (3)
- Smartlead :  → 
- HubSpot Marketing Hub :  → 
- AiSDR :  → 

_Unreleased versions with tentative dates are not included; see https://adstackwatch.com/deadlines/_