Maybe timesact will support this - not sure off hand though - https://apps.shopify.com/timesact-discount-pre-order - cool preorder app I’ve come across recently.
Topic summary
Issue: Google Merchant Center (GMC) removed all pre‑order products due to a mismatch—storefront shows “pre‑order” while the Shopify feed (Content API) reports “in stock.” GMC requires availability to match the product page.
Root cause: Most Shopify pre‑order apps enable “Continue selling when out of stock,” which makes the backend (and thus the feed) appear in stock. Timesact confirmed they cannot change feed availability under this model.
Proposed approaches:
- Use a feed app (e.g., Multiple Google Shopping Feeds) to read a metafield that stores pre‑order status and map it to availability=“preorder” in GMC. Also ensure structured data on the product page reflects the same availability.
- Use Google Merchant Center Feed Rules to automatically transform availability to “preorder.” One participant notes rules are automatic, not manual, but specific configuration steps weren’t provided.
Constraints: Manual edits in GMC are not viable with hundreds of pre‑order products.
Status: No confirmed solution implemented. The original poster plans to test the feed app; others asked for updates. Broader gap noted: no native Shopify method to align pre‑order status across storefront and product feed.