WoW prepaid time incorrect

This bug is easy to reproduce, but only happens if you have more than one PC that you use to play WoW. This only happens on an account that does not have a recurring subscription, but has prepaid time. If you mouse over the time remaining for your WoW account, it will show the correct end date. The problem starts if you leave the Battle.net client open on that PC, then go to another PC (e.g. go from office to living room HTPC) to log in there. When you get back to the original PC, it will have a Reconnect button. When you click the Reconnect button, the time remaining on your account will have decreased by some amount based apparently on how long you were logged in on the other PC.

Reproduction Steps:

  1. Prepare two gaming PCs with Battle.net client installed
  2. Prepare a WoW license with prepaid (i.e. non-recurring-subscription) game time
  3. Log into Battle.net client on PC #1
  4. Check the expiration date and time for the pre-paid WoW account
  5. Without closing the Battle.net client on PC #1, log into Battle.net client on PC #2
  6. You should observe PC #1 become logged out with a Reconnect button appearing
  7. Open WoW on PC #2 to log in with a character, and spend some time in the game
  8. Exit WoW on PC #2, and put the PC to sleep (S3 mode)
  9. Go back to PC #1, and click the Reconnect button
  10. Observe the remaining time on the WoW pre-paid account, and compare to the value from step 4 above