[QUOTE=dparkinson;16516506]Trying to go aaa-bbb on Sunday and bbb-aaa on Monday. However its much cheaper buying aaa-bbb Monday and doing sdc. If the flight times overlap will the computer cancel out my reservation?
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It is likely, so you might want to have the one one-way in UA and another in CO. This trick might work. Just make sure the one you are trying to SDC is booked at CO!!