I too am curious...I am guessing there are 3 different situations:
- Airline screwed up and transported someone whom should not have been
- Airline did not screw up but passenger was somehow denied entry
- This case where the rule is suddenly changed
Where is the passenger returned - native country, last boarding point, origin of the journey?
Who is responsible for the "return trip"?
In this case, I feel sorry for those who saved up the money to come to the US and only to be turned away. How are they going to be able to afford to make another trip [once they are allowed in again]?