I have some GPU's which expire at the end of January, 2014. I would like to use these on a flight in June, 2014.

1) To use these GPU's, does the booking/upgrade have to be before the expiration date or does the travel date have to precede the expiration? Is it even possible to use the January GPU's on a June flight?

2) I also have some other GPU's (and some RPU's) that expire in 2015. When I upgrade, is it possible to specify that I am using the earlier expiring GPU's?

3) At this point the flight has R9 for upgrade space. If for some reason the upgrade does not clear, will the GPU's be redeposited with the old expiration dates?