I am looking to change our FC tickets (paid $440 each), and know I'm subject to fare difference, so before I went to the AS website I checked the booking page. For my alternate day, 1 ticket is left at $365, but for 2 tickets it's $444 each, and I know that's how the system works. I wouldn't go through any hoops if it was a straight swap, but for the difference ($809 vs $888) I want to. Can someone please confirm if this is the correct way to do it:
1. Cancel original itinerary for two passengers, will result in two vouchers being issued
2. Book Ticket #1 with voucher 1, will have remainder $75
3. Book Ticket #2 with voucher 2, will pay $4 out of pocket.

And can anyone confirm if I'll have instant access to the flight credits to do this?