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
You can be caught if your seatmate believes that there will be an empty seat next to him/her. For example, some airlines and GAs will block seats next to elites when the plane isn't full. Nonrevs have been known to watch seat maps and ask to move up as soon as possible after departure.