There's no way to know without access to Disney's records.
Several years ago people staying at value resorts at a popular time used to pretty routinely get bumped over to SSR and complain about it on DIS, it seemed to happen about the same time every year too - which seemed suspicious to me.
Around that time I listened to Disney's stock earnings call & the CFO (Russo?- forget the guy's name) specifically stated that demand for WDW hotels tended to book deluxe/value first & that they'd overbook values knowing they would move them to moderates which tended to book last. I was a bit surprised to hear that statement as it basically admitted bad faith on Disney's part to enter into a contract to provide a room at a specific resort knowing they couldn't do so, not to mention laws against bait and switch.
It's one thing to move a value booking up to a moderate or deluxe - you'll probably find enough people happy with the upgrade that you can get away with it. I hope they aren't trying to increase revenues by overbooking the Epcot resorts during food & wine when those resorts are most in demand figuring they'll just move people to another deluxe as I suspect they'll face a lot more anger from their customers. I know if Disney had taken my money and then intentionally overbooked the resort they promised me I'd be livid.