When it could have been Ent-E at Frontier Day, Seven gets command of the Ent-F, and in Legacy, Seven could have been given command of the Ent-G. Just time skip a decade later for the latter.
Man, you gotta have a death wish to serve on an Enterprise.
I just pictured a row of cadets pissing their pants and crying when they find out they've been assigned to the Enterprise.