The following time-in-grade restrictions must be met unless advancement is permitted by § 300.603(b) of this part: (a)Advancement to positions at GS-12 and above. Candidates for advancement to a position at GS-12 and above must have completed a minimum of 52 weeks in positions no more than one grade lower (or equivalent) than the position to be filled. (b)Advancement to positions at GS-6 through GS-11. Candidates for advancement to a position at GS-6 through GS-11 must have completed a minimum of