Symptoms
Subscription is stuck in "Changing Plan" status. Subscription has a Switch Plan which has "Canceled" status.
In the list of Orders in the Provider's Control Panel:
Home - Operations - Orders
it can be found, that the last change to the Order status has been done by BA:
Order ID Order Type Order Date Status Wait Time Updated by
12345 Change Order 01-Sep-2015 Cancelled 125:17:38 system
Cause
Internal Issue: PBA-64327 "Subscription service status is left as "Changing Plan" after change order cancellation by billing"
Resolution
The fix will be included in one of the future versions of BA. To workaround the issue and change Subscription status, BA API call can be used, as described in the following KB:
https://kb.cloudblue.com/en/124493