When you get your souvereign to drink from a magical fountain, your maximum health goes up with 10 hp. Your current health stays the same, even when you are at maximum health at the moment you drink. Shouldn't your current health go up as well?
I mean, if the magic of the fountain is strong enough to make your maximum health go up, shouldn't your current health go up as well? Maybe relative to the difference between current health and max health at the moment you drink?