IMHO Nokia will not be able to switch to a plan B, when plan A fails, Nokia will be in a terrible state, Elop is doing a wonderful job of dismantling Nokia, killing and selling off everything that is a threat to WinPhone or has a chance of giving Nokia a recovery without Microsoft.
the new rumour is Microsoft is looking to help RIM, or as i see it Microsoft is look to make sure they kill QT so it has no future in the mobile world and can not be a threat to Microsoft's master plan.