Originally Posted by
C17MooseDriver
This is the rule of thumb that everyone in my squadron seems to be using. Because, all the hours you fly after upgrading to AC isn't all A Coded time. You've might have flown with another AC that was A coded instead, you flew an LTM and so forth.
Obviously, the best thing to do is to start keeping your own records early on, but not everyone thinks about it until it's too much a$$pain to go back. If you had an electronic logbook or even your own paper logbook, you could keep track of when you had the A code and when you didn't and log them PIC/SIC.