Conversation so far:
how many generals does the us military have
The U.S. Army has 315 General Officers.
how are generals nominated in the US
Generals are nominated for the appointment by the President with the advice of the Secretary of Defense, service secretary, and if applicable the Joint Chiefs of Staff
what is a general's standard tour in the US
The standard tour for most general positions is three years, bundled as a two-year term plus a one year extension
at what age must generals retire in the US
All generals must retire the month after their 64th birthday

Question: what is the maximum time the officer can be in service
Self-contained rewrite: what is the maximum time a general can be in service in the US