This occured on the Coirnav server with, I believe, 5 ranks of Flaming Arrow AA purchased and 0 ranks of Frost Arrow AA purchased. After the merger to consolidate Flaming and Frost Arrow AA lines, my character now has 0 ranks of the combined AA. I think I should have had 5 ranks of the combined AA rather than losing abilities that I previously had.
I had maxed AAs on The Nameless server, level 110 ranger, and after the patch I had 0 levels of the new consolidated flaming arrow.
Same boat, I had 5 ranks in Flaming and one in Frost. Lost all AA's. I just returned after a decade long break, and wrote in the issue and the response was it was because of the patch, and there would be no refund of AA's. Which is absurd, and I am not overly impressed with the new Flaming AA.
You should have a chunk of unspent AAs that match the cost of buying the new version. I had in excess of 500 saved when logging in (normally 330).
Same thing on coirnav. 3/3 of flamming arrows = 18aa 1/3 of freezing arrows = 3aa Logged in with 0/3 of flamming arrows and 0 AA unspent.
I suppose I should open a petition then, because I was not reimbursed. I was max AA before the patch with 348 banked, and after the patch, after maxing out the flame arrow AA again, I had 202 fewer banked AAs. It was definitely not AA-neutral; it cost me. I would love to be reimbursed even now, but it is not really that big a deal.