We bought 3 day non- park hopper tickets through
Undercover Tourist. We used them the 3 days of our trip (Dec. 19, 20, & 21st ). On the 21st, we went to Disney Studios during the day, then back again for Osbourne Lights & Symphony in the Sky. Once we went through the gate that evening, we went to Guest Relations and upgraded our 3 day tickets to Gold Passes. The wonderful CM did suggest we might want to wait until after the fireworks to upgrade, because technically we shouldn't be in the park because of being a blackout day once we upgraded, but two of us weren't staying for the 11:00 pm fireworks so she agreed to do it right then and just warned us if we left the park, we couldn't return. The next time I checked my
MDE, the Gold passes were on there. This is the only time we've ever done this and it worked just as described by previous posters. Thanks for all your help and guidance!