Everyone knows that Apple’s planning a big makeover for Apple Stores overnight Saturday into Sunday. Further, retail management meetings are scheduled for Sunday morning and fans, pundits and bloggers have guessed themselves blue over what they think’s coming.

Boy Genius Report started it all with the rumor that Apple’s Stores will be holding an overnight Saturday to Sunday work session. What could the mothership be up to?

The guesses have come in all over the map — iPhone 4S, Mac OS X 10.7 Lion, Apple Store 10th anniversary, etc.

AppleInsider thinks so, too.

However, I think it’s going to be something so much simpler and, frankly, more timely. The mothership’s kicked off their Back to School promo three Mays in a row and this year it’s going to be (queue booming reverb effect) bigger than anything they’ve done in the past.

No, I don’t have any inside information, but Back to School seems a more plausible reason given the timing and lack of hardware related leaks…

What’s your take?