Dan, (or anyone else), I understand that you were charged the full $300 right away, and will receive a credit from expedia within a couple of days. Have you been able to confirm what someone posted here, about Jetblue tickets, that they were only initially charged any amount 'over' $300, but if it was within $300 it got cancelled out, and were not even charged? My friend booked via Buf with Jetblue, and claims to only being charged $23.
Btw, thanks Aussie and Dan, but I didn't book myself, this time.