Bari to alto for three days?!

i don’t know if I’m allowed to post this on this subreddit but if not pls remove:)

Idk if this was fair of me to switch from bari to alto for three days. I’ve played alto and tenor for 2 years and started bari 4-5 months ago. Uhhh there’s this know it all alto player.. today I decided to play alto for the first time in 8 months, I used to play alto in the middle, but because I started playing tenor and bari I don’t do that anymore. My teacher prefers if altos play in the middle because it’s more casual, but he understands why I no longer play In the middle and because I broke my collar bone 3 months ago I no longer can wear the harness and now use a stand for it. The stand ended up breaking (it’s quite old and my director ordered a new one arriving in two days) and my tenor was left at my dads house (I’m staying at my moms) so I had no tenor so I grabbed one of the altos. I go to my usual spot (I would be playing bari line on alto). At the edge there is 4 altos then there’s the 2 tenors next to me (I’m more In the middle of the room). Then one of the altos are like “why is she playing alto and going to the middle of the classroom, it’s not like we get to change instruments whenever we want and go to a random spot. Instrument categories must stay together” so I move next to the other altos. Back to the side or middle situation, I started playing alto on the side because I wasn’t going to be playing alto for more than a day or two. The same alto that made the earlier remark just stared at me and said, “you’re supposed to play in the middle not the side, an alto is not a tenor or bari.” Honestly I don’t know anymore, I’m just trying to not re-injure myself and not miss my classes, is there anything wrong with that? I don’t know, should I just play in the middle for the two more days I’ll be playing? Should I just play bari with a neck strap?