Different Operating System ?

I want to load a "stock" non-modified tune - I think I found one - but when I tried to load it - it said "different operating system" so checking other buttons/options I see there is one to load tune with different operating system. Since I am totally newbie - I wanted to ask if there are any "gotchas" to this procedure? Will I be able to re-load my current loaded modified tune - after loading a base tune with different operating system number? Thank you in advance. :lookaround:

If your sure the OS will run the vechicle, your gonna have to do a full Flash?

And after you do a full flash with the different OS, your old tune file will not reload (i.e. it won't do cal-only flash)...

you have to manually copy all the tables from your old file to the new file.