When is it possible to run away?

[Vilk]

You also cannot run away from boss fights nor from some special fights. It's not that useless to run away, unlike the doc quote, the king will give you a sum of money proportional to the army you had.

I tested it multiple time and reach the conclusion that it's a possible way to sell troops you don't want use anyway.

My tests didn't show any limit in the number of flee but the sum the king gives you is smaller and smaller.