A FlyerTalk Posting Legend
Join Date: Sep 2009
Location: Minneapolis: DL DM charter 2.3MM
Programs: A3*Gold, SPG Plat, HyattDiamond, MarriottPP, LHW exAccess, ICI, Raffles Amb, NW PE MM, TWA Gold MM
Posts: 102,617
I've been told that DM agents have a bit of leeway on the expiration dates for SWUs, but apparently once they disappear from your account and you can't recover the numbers and codes, they're gone.