The Defense Advanced Research Projects Agency (DARPA) is hosting a Grainy Day Proposers Day on June 30, 2025, in Arlington, VA, to inform potential proposers about an upcoming Program Solicitation (PS) for the Grainy Day program. The event aims to outline program objectives, explain DARPA's operational processes, and promote collaboration among cleared and uncleared organizations with relevant expertise in sensor deployment from Unmanned Aerial Vehicles (UAVs). The event will include SECRET-level discussions while also featuring UNCLASSIFIED Lightning Talks for those without security clearances to engage and present their capabilities. DARPA is specifically seeking innovative solutions for the deployment of unattended sensors in challenging environmental conditions, emphasizing areas such as aerodynamics, microelectronics, and manufacturing. Registration for the event is required, with strict security protocols in place for both cleared and uncleared participants. Furthermore, the document stipulates that the Principal Investigator must possess an active SECRET personnel clearance, underscoring the classified nature of the program. Overall, this Proposers Day is intended to foster innovative partnerships to address technological challenges in sensor delivery systems while ensuring compliance with security requirements, crucial for future proposal submissions in response to the anticipated Grainy Day PS.