Expanding Access to Child Care for Military Families Act of 2024 This bill requires the Department of Defense (DOD) to direct the military departments to implement a pilot program to improve the access of members of the Armed Forces and their families to high quality early child care opportunities. Under the pilot program, the military departments must establish partnerships with 12 child care providers to (1) increase the capacity of the providers, (2) improve early child care workforce development, and (3) increase recruitment and retention of employees for eligible child care providers. Child care providers under the program may not reduce early child care slots for nonmilitary families after entering into the partnership or enter into the construction of new child care facilities. DOD must direct the military departments to provide annual briefings to Congress on the implementation of the pilot program. The Government Accountability Office must submit an interim and a final report on the progress and results of the pilot program.