Unfortunately, I can't offer any advice, other than what I offered above. In all of our testing, the only time the store 'got stuck' like that was when the device's clock had been set backwards, and the game was launched while the time was earlier than the last time the game had been played.
There was a bug in the Windows version of iTunes that would randomly change the date and time on the device (see
this answer in our Support FAQ for more information), but I don't know if that applies to you.