Different headhunters reaching out to different people at same firm?

Hey everybody, currently working as a first year in an MBB shop in a non-PE heavy city (big city but not NYC, SF, Chicago). Headhunters have started reaching out, but different people within the office and people across nearby offices have been getting different headhunters reach out. This is the case for HHs for MFs and HHs for more MM opps.

I was wondering two things: 1) how do headhunters decide who they reach out to other than by firm/school? My colleague who did AM and went to a non target school in a nearby office is getting many more PE headhunter emails than people I know who did SA at BB/EB

2) is it appropriate to reach out proactively to a headhunter if you know they’ve contacted people at your firm? I would hate to miss out on events and the like especially if PE recruiting is so accelerated

3) has anybody here heard of firms blocking headhunter emails? One headhunter suggested this was the case

Thanks! Looking forward to hearing your insight on this one, I’m very confused on how to navigate this process.