Hello, I'm waiting for my spark (it'll arrive on monday). I've been reading a lot around here about the FCC (I live in Europe) and OTG and I have a very important question for when I start with my fresh drone: Should I upgrade the spark and remote's firmware if I'm warned to do it by the DJI GO 4 app(4.2.8) if I want to go back later to 4.1.15? (I think I would like to start with the latest version of the app, and when I'm ready switch to the mod so I can activate FCC. That's why I want to be sure that latest firmware will not prevent this to happen...) Thanks a lot !!!!!