Under uniform regulations prescribed by the Secretaries concerned, a member of the Ready Reserve who is not a member of the National Guard or of the Selected Reserve is entitled to an allowance for muster duty performed pursuant to section 12319 of title 10 if the member is engaged in that duty for at least two hours.

The amount of the allowance under this section shall be 125 percent of the amount of the average per diem rate for the United States (other than Alaska and Hawaii) under section 452 of this title as in effect on September 30 of the year preceding the year in which the muster duty is performed.

The allowance authorized by this section may not be disbursed in kind. The allowance may be paid to the member before, on, or after the date on which the muster duty is performed, but not later than 30 days after that date. The allowance shall constitute the single, flat-rate monetary allowance authorized for the performance of muster duty and shall constitute payment in full to the member, regardless of grade or rank in which serving, as commutation for travel to the immediate vicinity of the designated muster duty location, transportation, subsistence, and the special or extraordinary costs of enforced absence from home and civilian pursuits, including such absence on weekends and holidays.

A member who performs muster duty is not entitled to compensation for inactive-duty training under section 206(a) of this title for the same period.