I've seen regular subs (not finish the fight or green gate sub switches) that normally have 4 or 5 gates become 2. It also is usually accompanied with a weird ending where the sub completes in the middle of a gate. Might be damage, lag, or a bug. Haven't quite put my finger on it.
I think I’ve had normal subs (not ftf or green gate) that were 2 gates also. It was only once offline and I don’t record stuff. I thought oh well someone else will report this.