(b)
Notwithstanding
section 5536 of this title, an employee entitled to the benefits of subsection (a) of this section while on a vessel, may be paid, in place of these benefits, an allowance for quarters or subsistence, or both, when—
(1) adverse weather conditions or similar circumstances beyond the control of the employee or the Corps of Engineers prevent transportation of the employee from shore to the vessel; or
(2) quarters or subsistence, or both, are not available on the vessel while it is undergoing repairs.