I think the OP is asking about the protocol for swapping seats with her husband so she sits in Y and he gets her F seat; she wasn't suggesting just moving him up front with her. It seems to be pretty common to make such a swap, but I've not done it myself.
If you are on paid tickets, not award tickets, your husband is eligible for a companion upgrade. Maybe that will happen at the 24-hour window, which would be the best solution of all!