Originally Posted by
Tafflyer
If you are through ticketed on a J or F fare then you are entitled to domestic F if available. If you still booked a sector where it was not available, then that was your choice at the time. Any change later would be subject to the terms and conditions of your original booking, ie. change fee. However, if the airline cancelled a sector and rebooked you on a sector where F is available, then that is IMHO what you should get.
It comes through as a cancellation and rebooking, but flight number and times are exactly the same (as the amended flight from the previous email an hour or so before).