What are the requirements for a LoA/how do you see if you qualify?

I’ve been at SB for over a year and am a PhD student. It’s been fine while I’ve been working from home, but now I’m back to teaching in person AND working on my dissertation. It’s simply too much with SB, as well. I’d like to do a LoA, as I like my manager and team, and it works well with my schedule during breaks and stuff, but if it’s not possible I’ll simply have to quit, which is fine, too.

My manager is getting married soon, so I’m trying to minimize badgering him. :)