What fleet growth requires another admiral

What must be added to a navy before it needs another flag officer?

The need arises from additional independent formations, task groups, major decisions, and procurement responsibilities rather than a fixed number of hulls.

Independent ships can sometimes operate with little extra senior command, while multiple task groups and fleets create recurring decisions that require flag officers. Large procurement portfolios also justify experienced leadership because someone must direct the acquisition of expensive warships and the organizations that support them.