14 U.S.C. § 746 : US Code - Section 746: Recall of a retired officer; grade upon release

Search 14 U.S.C. § 746 : US Code - Section 746: Recall of a retired officer; grade upon release

(a) When an officer in the Retired Reserve or an officer on a
Reserve retired list is recalled to active duty, that officer shall
be recalled in a manner similar to the recall of a Regular retired
officer.
(b) An officer in the Retired Reserve or an officer on a Reserve
retired list recalled to active duty shall upon release therefrom
be advanced in the Retired Reserve or on the Reserve retired list
to the highest grade held on active duty, if: (1) appointed to a
higher grade while on that duty, and (2) the officer's performance
has been satisfactory in the higher grade.