Slitherine

It happened moments ago: end of my turn, I press the end turn button. One of my Thessaly light cavalry almost surrounded by Galatians heavy troops then breaks-off.

Good.

But right after that (and while it is still technically my turn!) one of the galatian light infantry close-by to its new position rushes to contact it ! No fight, but they are in melee already...

Is that normal that a non-active player has troops chasing after a break-off ?

Sure the horse wasn't routing and the LF was following up? I don't think anything can pursue or move during break-offs.

Absolutely sure!

My light cavalry was not routed and the light infantry wasn't even in melee with it !!!

The light infantry was somewhere in between the enemy line and my line. My light cavalry was fighting his line of heavies. My cavalry broke off towards my line. And then the enemy light infantry walked 1 or 2 hexes just to contact my cavalry again...

Weird!

hmm...definitely. I have never seen anything like that.