Join Date: Apr 2009
Location: Bye Delta
Programs: AA EXP, UA Silver, HH Diamond, IHG Plat, Hyatt Plat, Marriott Titanium, Nat'l EE, Avis PC, Hertz PC
Posts: 16,614
iPhone or Android? If iPhone, you can delete the boarding passes out of your wallet and re-download them.
There are other reasons I’d want an up to date BP, but even if you used the old one, it’d be perfectly fine. The only thing that would happen is when you scanned at the gate, the computer would alert and the GA would print you a boarding pass with your new seat.