The Defense Advanced Research Projects Agency (DARPA) will host an in-person Proposers Day in support of the Program Solicitation (PS) for RF Architectures Applying Photonic Timing and Routing (RAAPTR) program on June 16, 2026, at Amentum Services, Inc (4121 Wilson Blvd., Suite 200, Arlington, VA 22203) from 9:00 a.m. to 5:00 p.m. ET. Participants must register for the RAAPTR Proposers Day through the registration website by June 8, 2026, at 11:59 p.m. ET. DARPA anticipates releasing the RAAPTR PS sometime after the Proposers Day. If released, the PS will be made available at https://sam.gov/.