when I was going through my out of town transfer a couple of months ago. My clinic recommends 36 hours of bedrest, but retrieval and transfer were a day later than expected, which meant that I would have had to change flights to get the full 36 hours.
In the end I decided not to come home on a later flight - I only had 15 hours of bedrest. My clinic (whom I love) admitted that the research does not necessarily support bedrest, but they wanted to be cautious. They asked that I stay hydrated and recline as much as possible on the plane, not lift heavy things, and not do anything to raise my body temperature (exercise, hot bath, sauna).