Feel like in the AI age, the optimal size for a team of devs on a single decent-sized project is around 3. 1 is untenable. You can't just pause development during their holidays. 2 is OK, but still a lot of bus factor to contend with. 3 is nice and comfortable. Each day the team manages the queue of tickets for the AFK agent, discusses feature requests, architecture, reviews code, improves feedback loops, shares knowledge. Probably some devs contribute to multiple teams.