Deprecation of the Checkout API - Offsite Payment Apps

[Snappy_uk]

Hi, Has anyone found a way to get the Checkout information (line items etc) in the offsite payment gateway flow after Shopify deprecate the Checkout API in April 2025? I cannot see a suitable replacement in the migration documentation and the StoreFront API (which is the suggested replacement) doesn't allow us to do the same thing. Currently we are using the below API call:

https://${store}/admin/api/${api_version}/checkouts/${checkoutToken}.json - GET

Is there a suitable alternative which can be used in Offsite Payment Apps. This will break our current app in April 2025 if we can't find a replacement.

Any help would be appreciated, Thanks!