How quick can your earn your specialist rank?

Answer:
This may have changed, however when I served....

E1 to E2 was six months time in service.
E2 to E3 was one year time is service, six months time in grade.
E3 to E4/SP4 was eighteen months time is service, six months time in grade, and recommendation of an E5 or higher.

So no less than eighteen months, provided you earn good reviews and have no disciplinary action.
Contributor: C.Hainsaw
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