if I disable donations and loose the current members of the group.
Current subscriptions within an inactive group will continue until their subscription runs out, or until they are manually removed from the Permission Group.
In other words, if you disable a subscription, it will only prevent users from creating new subscriptions to it. All members in that group will remain in that group until their agreed subscription date expires, no matter if that subscription is active or not. Disabling a subscription group will just disable new subscribers from joining it.
TIP: If you have a large group of users in a subscription group that will expire at different dates, and you no longer want that subscription group to have any expiration:
1. Create a new group (SUB NEW) with all of the old group's permissions.
2. Perform a custom search for all of the users in the old group (SUB OLD). Copy/Move them to the new group (SUB NEW).
3. Disable that old subscription (SUB OLD)
RECOMMENDED: Rename your old subscription group (SUB OLD) so your transaction history now reflects that the payments you received at one time, belonged to the subscription that you no longer provide. Also email everyone that was in the old subscription group (SUB OLD) that because of their past payments, they have now been "grandfathered" in to the new subscription (SUB NEW), which is exactly the same as old subscription name (SUB OLD) which will go away on its /natural expiration date/.
Basically, "You've been updated to a permanent status which includes all of the features of old group. Previous subscription with this name will be displayed on your transaction history in name-only. They will not affect your access or the service we deliver to you."