Lucky Foot Question?

I used a lucky foot during a battle but after attacking a few times I ended up fleeing from the battle by mistake. ^^; However I have a banner that says the lucky foot effect is still active. Is the effect supposed to not get used up if you flee?

I've heard people say it doesn't have to expire. I think it defninitely expires when you win a fight (or it always does for me) but it can stay active when you retreat.

Lucky foot is used when you either win or lose a battle. It you retreat the lucky foot buff is not used up.