Subscription terms. 'plan' in recurring tells a merchant-declared
subscription line (StoredLineRecurring) from the plan line a checkout
session adds (LegacyLineRecurring). Null on a one-time line.
referenceId
referenceId:string|null
subscriptionId
subscriptionId:string|null
The subscription this line created. Null until the checkout completes.
Subscription terms.
'plan' in recurringtells a merchant-declared subscription line (StoredLineRecurring) from the plan line a checkout session adds (LegacyLineRecurring). Null on a one-time line.