Yes, ausf. (ausführung) is German for 'model' or 'mark'.
In my Ch. H, the illustration of the back-side of the PzIVF2 (p. H14) and the vehicle listing chart (p. H10) shows only A5 '42. My actual ctrs (from BV 1st ed.) have A5^2/4^3, & the rarity factor chart (Ch. H divider) shows the PzIVF2 unavailable after 12/43, which seems unlikely to me!
Only 175 F2's were made, from March to July of '42. The ASL ctr also probably represents that half of the PzIVG production which was made w/o the add'l bolt-on armor, the up-armored IVG's are represented by the PzIVH ctr.
What does your Ch. H have to say? Since there seem to be 3 different answers to this question, mebbe drop Perry a line to get the true picture.