Shop.billingAddress uses new type, deprecates name fields
API
Effective January 01, 2023
As of 2023-01, the Shop.billingAddress field uses a new ShopAddress type instead of the customer-centric MailingAddress type.
Since Shop.billingAddress never returns non-null first or last names, these fields have been marked as deprecated on the new ShopAddress type. You should stop requesting those fields as they will be removed in a later version.