Join Date: May 2004
Location: SIN (LEJ once a year)
Programs: SQ, LH, BA, IHG Diamond AMB, HH Gold, SLH Indulged, Accor Gold, Hyatt Discoverist
Posts: 7,741
Sometimes, in the old days of high occupancy and such, I would email the hotel in advance advising of the different reservation numbers and request the same room to be assigned. Shouldn't be so much of an issue these days, but it can't hurt either in my book. As others shared though check in should be able to sort it out as well. YMMV.