DOD Transfer and Reprogramming Authorities: Background, Status, and Issues for Congress [June 17, 2020] [open pdf - 2MB]
From the Introduction: "This report provides information and analysis on DOD transfer and reprogramming authorities, as well as reprogramming actions. This report does not cover functional transfers--that is, funding realignments to reflect a transfer of function, responsibility, or duty from one major command to another within a military department or defense agency."
CRS Report for Congress, R46421
Congressional Research Service: https://crsreports.congress.gov/