From 1975 to 2014, Petitioner David Babcock (“Babcock”) was employed as a National Guard dual-status technician. Babcock v. Comm’r of Soc. Sec. at 1–2. A dual-status technician, under 10 U.S.C. § 10216(a)(1) and 32 U.S.C. § 709(e), is “‘a [f]ederal...