Gabby6z: My brother priced a fairly cheap BusinessFirst fare and said the fare code was "Z", wanted to find out if it got miles. I'll e-mail him and find out who he used. My guess is 1st-air.com, but I'll find out.
I just noticed on the CO BizFirst website:
A BusinessFirst mileage bonus of 50% when you fly First Class (A), Business Class (C and D), BusinessFirst (J) and published fares in Z class.
So "Z" does earn the 50% bonus...