Tenure group I applies to employees in the competitive service under career appointments who are not serving probation and permanent employees in the excepted service whose appointments carry no restrictions or conditions.
Tenure group II applies to employees in the competitive service serving probation, career-conditional employees, and career employees in obligated positions. It also includes employees in the excepted service serving trial periods, whose tenure is indefinite solely because they occupy obligated positions; or whose tenure is equivalent to career-conditional in the competitive service.
5 C.F.R. §340.202