Join Date: May 2004
Location: formerly Gold now Diamond, formerly MSY, now LAX, formerly NW, now DL
Programs: Hyatt Plat, Hilton Gold, SPG Gold, Delta Diamond/1MM
Posts: 4,724
IIRC on Delta you can't standby or upgrade on LUT fares either.
NW has similar policies as CO, though I believe the window to rebook is larger.