Groomsmen

This doesn’t need to be decided until it’s time to order their attire, so maybe 2-3 months before the wedding.

They do need to be asked before invites go out (which is 8 weeks out) and given enough time to schedule time off from work and not interfere with other plans. 6 months out is fine.

I think that’s still pretty early on to need to decide but I wanna say I agree with pp that six months seems good

This isn't a huge deal yet. I agree with PPs - 6 months is fine.

I totally understand your frustration. My FH took a long time to pick his final groomsmen. I would say as long as they are selected by 6-8 months out, you should be okay. Most of the checklists don’t order the guys attire until 3 months out but I’m adding extra time due to our current situation.
Deep breaths! It’ll work out and be glorious 😁

That's a LONG time from now! Anything can change in 10 months, let him takes his time. We are getting married in 4 months, and my fiance still has not finalize who will be his groomsmen especially there's a pandemic going on right now.