This has been around a loooong time in my republic(s?), no idea how long. As 0 is far right, I hardly get to use it, but when even 2 years back in s1 I tried assigning helicopters there, they never managed to stay assigned to to menu and got thrown out.

I am in s3 now, 140 episodes in, full republic. Again I wanted to use "0" group for the final city I am developing, as I saw that in someones videos he uses it and it works. It worked for a while, but yesterday it started discarding all 3 assigned offices to this group to a point they all disappear suddenly at once, without pressing any button or so.

This is the only group that does this, all other are fine (1-9). I have no idea why this happens, but it forced me to merge groups 8+9 together to free 9 for this task. There these offices work fine again.

I have no idea what is happening, but you should probably know that :D