[throwmeaway32]

First off, managing people is not a 'promotion', it is a complete job change. It is not a incremental increase on previous skills or job expectations; it is radically different and you must be aware of that if you want to succeed.

If the company considers a move from a individual contributor to a people manager a promotion then it is disfunctional.

Ignore this whole concept you have of 'playing politics right', you have wayyyyyyyyyyyy more important things to deal with. 8 devs will keep you very busy with 1:1's, career guidance, mentorship along with day to day running and long term more strategic less tactical planning.

Reset your expectations on the problems you will face and have to consider; your entire world is about to change (if you want to be a decent manager).