This is exactly what I am planning do next month. Renew our gold APs and use MYW tickets towards the cost of the renewal. I am not using the tickets first because our APs do not expire until a few days after our trip ends. I hope we get a CM who can do the quick upgrade for us. Will report back after our trip.
I'm curious how you made out? I'm planning on buying 10 day park hopper from AAA. In addition, we get a small employee discount on top of AAA price, 3 or 4%. Plan is to use ticket first day enter park, go to window to upgrade to AP and pay with Disney gift card that was purchased from target 5% discount. Fingers cross this all works.