Do trenches only change hands during offensives?

[Mongoose McMoose]

Ran into an interesting issue where a small forward trench I made branching off my first trench line was 50% taken during a german offensive, and when the offensive ended about 5 or 6 of the trench squares remained german while the other 10 or so remained british.

The issue is now that every german unit and every british unit rushes into that area, becomes quickly exhausted, cannot be moved out of that area, and combat cannot really happen because combat effectiveness for overstacked squares is essentially 0%. I've seen squares with 20+ units from each side sitting there unable to fight because the square is overstacked, and if I move a fresh troop into that square they are also 100% ineffective because of the overstacking penalty. They "attack" but cause zero casualties because of the debuff, exhaust themselves because they are allegedly fighting, and they are once again stuck in that square.

I can't bombard the square because it would kill all my troops as well, I can't seem to get units to engage with rifles or MG's for some reason, and grenades also kill my own troops. But no matter what I do, the square will not flip back to british, so the AI for both germany and me continues to push in troops, so game over I guess.

Thoughts?

[Aggroblakh]

That sounds like an interesting issue - I'd be interested in seeing the configuration of trenches that led to this. Can you please send the save file to [e-mail]? I can probably reproduce a similar situation myself, but I'd like to fix your specific issue if I can.