Seems like we´re dealing with little children in this thread...the size of the A319 has nothing to do with "pilot qualification", but only with "contract" between VC (Vereinigung Cockpit = LH Union) and LH, about the size of aircraft to be crewed by non-LH pilots operating LH-flights...simple enough?
Did you ever see an Alitalia Express pilot command an AZ B777? Or, for that matter, an Air Alps pilot, or a Minerva pilot, or...?
Didn´t think so!