It's possible to delete (or edit) credits or class passes from your selection. Credits already purchased by yogis remain unchanged after an edit, will not be edited retroactively, and will not be deleted either.
When credits have been deleted, it's not possible for yogis to book a class with the deleted credits. This becomes an issue when yogis are still using the credits. That's why we always advise you to temporarily uncheck the Yogis can buy these credits online box when deleting credits for as long as they're still in use.
This way, the yogis cannot purchase the credits online anymore but still valid for the yogis using the credits. When the credits expire for all yogis, you can permanently delete the credits from your selection.