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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
Usually prepaid is cheaper, which is why people choose it. If the OP had selected prepaid at the time the reservation was made, presumably the rate would have been lower.