[jwells880910]

Could you not handle it like this:

Do a check if player completed the "diving" quest if true then toggle a setting from 0 to 1
Do a per map "can fly" setting in which either developers can use to "trigger" fly functionality in the appropriate map. this way all you would have to do is handle transitions between the 2? but from the previous 2 pieces of data its possible determine what state the player is in

For example:

Diving Unlocked -> Player Underwater -> Goes to Surface -> No Fly = Player Demounted
Diving Unlocked -> Player Underwater -> Goes to Surface -> Fly Unlocked = Player Mounted
Diving Unlocked -> Player Above water -> Goes into water mounted -> Fly = Player mounted
Diving Unlocked -> Player Above water -> Goes into water mounted -> No Fly = Player De-mounted

Then you have the common unmounted options which wont have to take into consideration "demounting"

i know its a clunky work around but would something like this not be useful this way you can do a "complicated" if statement or something like this.