Originally Posted by
aaupgrade
Splitting it into 2 reservations would eliminate the ability to check out 2 days early within the 5 day stay period without incurring a cancellation fee on the second reservation.
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IME when checking out early I have not run into any problems, even letting them know the day I am checking out.
The only times I can remember having troubles trying to check out early were at resort properties. So while you are may be right in that checking out early won't be an issue, it is possible it could be. By having two reservations, the OP can still cut loose the 2nd reservation as late as the check-in date with no issues.
If the OP isn't sure whether s/he will know the real check-out date even as late as the check-in date, then maybe a call to the hotel could help things out. Ask the hotel GM or manager if there would be a check-out "early" fee. If not, then your approach should be fine. If there is, then maybe mine or a different approach would be better.