I know, that it is a bad time to go on a long time vacation, as you have to "strike the iron as long as it is hot". They are in a upward trend, but...
What if they would be in the opposite situation and the company would be on its way down? "You can't leave now! We are losing our assets!" And if Everything would fine and dandy? "You can't leave, as we have to be on the watch right now. It is a dangerous situation." Well, I guess as every time is a bad time anyway, she can take her leave time now. Actually, as the company did so well because of her, it's the best time for her to leave. If the company suffers it is the fault of everyone who stayed, not hers. XD