A model may not fly high unless it is already on the table at the start of the turn. A model cannot therefore begin the game flying high. Similarly, a model cannot fly high on any turn in which it re-enters the battlefield, for example if it pursued an enemy off the table.

A model may not fly high if it is subject to some compulsory movement rule or a rule which prevents it flying. For example, if engaged in combat at the start of the turn, if fleeing, when pursuing, or if it is in a wood and therefore unable to fly.