5 C.F.R. § 630.406
Use of sick leave during annual leave
Subject to § 630.401(b) through (e), an agency may grant sick leave to an employee during a period of annual leave for any of the purposes described in § 630.401(a).
Subject to § 630.401(b) through (e), an agency may grant sick leave to an employee during a period of annual leave for any of the purposes described in § 630.401(a).