It's very inconsistent from property to property. I've been told by the front desk of a Comfort Inn in Myrtle Beach that they were required to honor a late checkout request, a Sleep Inn in Georgia gave me a late checkout without me asking("oh-you're CP, you can stay till 2"), and a Sleep Inn in Columbia wouldn't go past noon and didn't even want to go that late. Your best bet is to request it at check-in from the night desk clerk as the day shift folks are more interested in getting you out the door and the room turned around and will try to get you to settle for noon or 1pm instead of 2pm.