Originally Posted by
mendy7511
I did it on Sunday at YYZ at the transit counter. It took about 20 minutes and 3 agents conferring with each other as nobody knew how to do it or if it was allowed.
For some reason they where only able to put me in Y (I had upgraded the original flight) but the GA was able to switch it back to J, which incidentally was not full with 3 empty seats.
Good luck finding someone at LGA knowing what to do.
I think OP is flying YYZ-LGA, so it should be done at YYZ.
I did it once for a YYZ-YUL at the check-in counter, and the agent was very quick. I was on a confirmed upgrade. When boarding was about to start for the earlier flight, I went to the gate, and the agent called my name and gave me a new BP for J. It was a pretty smooth experience