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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
The PENALTIES section says that the tickets are nonrefundable.
BTW, most tickets are nonrefundable, especially cheap coach fares, although they're generally changeable without fees and can be cancelled for a credit (also without fees).