There's definitely something odd going on. The next turn was played out and the same thing happened again - same unit too. I could post the screenshots, but I'm sure you believe me
If the developers want to look at the game it is a 600 point DAG game Morbio (Seleucid) versus pcaravel (Macedonia). It's now over so it'll be there for a while....
Just for the record, the auto rotates weren't the reason I lost....
P.S. The replay is somewhat screwy at the start. It shows the cavalry in their break-off position (as at the end of the turn) and so the initial melees look odd with a pike BG hitting a Cat that's about 5 hexes away!

There's a couple of instances of that at the start!