Page 19 says that, about flying:
"If a flying creature makes a melee attack against a non-flying creature, it loses the flying trait until the end of the attack..."
So, against conjurations, it doesn't lose the Flying trait? That seems odd, since many conjurations appear to be small and close to the ground like a Mana Flower, and thus easily guarded, while others appear to be large, like temples or spawnpoints, and thus more difficult to guard, but it's hard to judge just how large conjurations are due to the art.
Seems kind of important to know for sure, since scale isn't clearly defined.