For example when someone is upgrading a KC-135A to a KC-135R, or in my case there already is data for the particular tail # of F-16 that I have, but the data is for the active F-16A, I have pictures of it as a QF-16A

I was thinking at first linking profiles, but they never changed serial number or owner and there is no option in the link for conversions of an air frame. I don't want to do it in data corrections either since the original data wasn't wrong to begin with.

Maybe the profile could be upgraded to the new profile and the original profile be added to the "Comment on this aircraft" section. That way they would both be listed for the aircraft.

3 months later

FM, I usually just create a new profile and link them like you mentioned. C-5A's going to M's, A-10A's going to C's and such.