(a) Other rates of tax on individuals, etc. (1) For rates of tax on nonresident aliens, see section 871. (2) For doubling of tax on citizens of certain foreign countries, see section 891. (3) For rate of withholding in the case of nonresident aliens, see section 1441. (4) For alternative minimum tax, see section 55. (b) Special limitations on tax (1) For limitation on tax in case of income of members of Armed Forces, astronauts, and victims of certain terrorist attacks on death, see section 692.
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