How do you cancel a prepaid subscription but still allow role-based access through remainder of license duration?

On a site that sells asynchronous prepaid role-based monthly subscriptions, our customers need to be able to cancel their subscriptions but still have access to the site until their existing prepaid license expires. Therefore their subscriptions should not be prorated.

I haven't been able to find documentation or a tutorial or really anything that explains how this can be done.

I've tried a number of things, but none of them quite work:

• Suspend the license
  The customer's role access is immediately revoked. The orders and billing cycle are not changed. The customer continues to be billed which is obviously not good. To add insult to injury, the new recurring orders do not reactivate the license.
• Revoke the license
  The customer's role access is immediately revoked. The orders are not changed. The current billing cycle's status is set to 0. The customer is billed one final time.
• Delete the license
  The customer's role access is immediately revoked. All of the customer's orders stemming from that license are deleted. The customer's billing cycles stemming from that license are deleted. Consequently all order and billing history is lost; it's as if the customer had never been a subscriber in the first place.
• Cancel both the "Recurring: Open" and "Pending"/(or "Recurring: Payment pending") orders
  The license is revoked the next time cron/advancedqueue runs regardless of how much time remains in the license or billing cycle. (FYI as far as I can tell, the "Pending" order is the original order before its status changes to "Completed.")
• Cancel just the "Recurring: Open" order
  The license stays active. When the current billing cycle ends a new "Recurring: Open" order is created. The customer is billed again. A new billing cycle is created. The accompanying "Pending"/(or "Recurring: Payment pending") order is eventually marked "Completed."
• Cancel just the "Pending"/(or "Recurring: Payment pending") order
  The license is revoked the next time cron/advancedqueue runs regardless of how much time remains in the license or the billing cycle. When the billing cycle ends, cron/advancedqueue attempts to deal with the accompanying "Recurring: Open" order but it can't because of non-object errors that occur inside billing_cycle_close_queue_process(). The existing "Recurring: Open" order remains open (and a new recurring order is not created). The customer is not billed again.