Downgrade is possible to ANY version but the official app (Assistant) does not support this. Maybe somebody will delete my post however you should all know that DJI using GPL licenced code in their drones they are violating the GPL licence with prohibiting free upgrades/downgrades which clearly states that the user must have the right to go back to factory state for free under any circumstances. There is ongoing comm with DIJ right know. Currently downgrade is only available for skilled IT people as you have to use coding and command line to achive it however there are clever guys out there already working on the 'easy' windows graphical user interface version for the community. This forum has it's own rule set and prohibit to discuss or link anything mod related so use google and your brain and other forums because it is really restricted.