New fields for custom attributes added to subscription contracts
API
Effective April 01, 2022
As of the 2022-04 version of the Admin GraphQL API, the customAttributes field will be present on the SubscriptionContract, SubscriptionDraft, and SubscriptionDraftIndex objects. Those new fields correspond to the existing field of the same name on the Order object.
This allows you to update a subscription contract draft with new custom attributes. Those attributes will be copied over to new orders created from that subscription contract.
Learn more about SubscriptionContract and subscriptionDraftUpdate on Shopify.dev.