At what point does the manager fire you and just let the AIs have at it ;)

Nah, you never voluntarily reduce headcount. Headcount is what keeps your salary coming. Any manager worth their salt would use this newfound productivity to infringe on other teams' domains: Hostile Takeover => More Headcount => Promotion. We'll see a lot of attempted empire building over the next couple years while all this gets sorted out.

Realistically, none of the models can function fully autonomously at this point. You still need a skilled human at the helm. However, AI tools definitely change how the human works. I find that I spend a lot less time thinking about easy things, and a lot more time thinking about hard things.

Basically, the AI fast forwards through the easy stuff and I just spend all day jumping directly from hard problem to hard problem.