Attempt to manually change expiration date for subscription fails with error:
You may not change the Expiration Date on this Subscription
By design it is possible to change expiration date only for Active or Expired subscriptions. Possible reasons of the error:
- Subscription in question is Trial.
- Subscription status is "Graced".
- There is a feature request #PBA-60451 ("Ability to change expiration date of trial subscription") to implement possibility of changing expiration date for Trial subscriptions.
- Update status of subscription to
Activewith SubscriptionStatusUpdate_API and then change expiration date.