***ONLY SEAPORT MAC HOLDERS ARE ELIGIBLE FOR AWARD UNDER THIS SOLICITATION.*** Request for Proposal (RFP) N6133126R3101 under the Seaport NxG Multiple Award Contract (MAC), for LCAC C4N and Cybersecurity Systems Program Support. This RFP will also be posted within the Seaport NxG Opportunities Page. This effort has been previously been posted within the Seaport NxG portal under the Opportunities page as the following: Sources Sought Notice N6133125SNQ18, dated 1/23/2025 and the follow-up Advance Planning Notice/Pre-Solicitation Notice dated 4/7/2025. Previous references to this potential solicitation were numbers N6133125R3006 and N6133126R3008. The date issued on the solicitation lists 12/29/2025 instead of 12/30/2025 due to document generation error. ***RESPONSES MUST BE SUBMITTED VIA THE PIEE SOLICITATION MODULE.*** ***ALL DOCUMENTS ARE AVAILABLE WITHIN THE SEAPORT OPPORTUNITIES*** ***Q and A WILL TAKE PLACE THROUGH SEAPORT NXG OPPORTUNITIES AND POSTED TO PIEE SOLICITATION MODULE BY ATTACHMENT*** Please refer to the Amendment Log found within the Seaport announcement for updates to the RFP. Update 0003 is not an amendment to the solicitation. Update 0003 corrects the submission response time in the PIEE solicitation module to 1600, as stated in the solicitation and SeaPort.