The F-35 program has accomplished the final developmental test flight of the System Design and Demonstration (SDD) phase of the program. The developmental flight test program has conducted more than 9,200 sorties, accumulated over 17,000 flight hours, and executed more than 65,000 test points to verify the design, durability, software, sensors, weapons capability and performance for all three F-35 variants. https://www.f35.com/
Source