OPM guidance on partial agency shutdowns induced by appropriations lapses outlines several areas of management discretion beyond the initial determinations of which employees are put on unpaid furlough and which are to be kept at work (“excepted” employees) despite the lapse.
Each agency determines the method and timing of notifying employees of whether they have been designated as excepted. “Advance written notice (including through email) is preferable, but when prior written notice is not feasible, then any reasonable notice (e.g., telephonic, oral, personal email, or by mail promptly after the furlough) is permissible when the furlough decision is made. However, a written notice of decision to furlough must be provided as soon as possible after the furlough begins,” it says.
Agencies at their discretion can call back employees who have been furloughed in order to accomplish certain work tasks.
For excepted employees who are on a detail to another agency, the two agencies should consult to determine what activities are appropriate for the employee to be performing consistent with that designation.
Agencies may allow excepted employees to take brief periods of time off during the shutdown period although if they do, the employee must be put in furlough status for those periods.