Bismarck.Dracondria said:
»Months? wat
I imagine he means no aby burning and by 99 he means capped skills and relevant gear.
I would 2nd that as well, within a few months you could take a character that had most old content complete (sea/sky access, rank missions, etc) to a good place in current endgame. It would be enough time to level, cap skills, do AF3, climb and collect relevant VW pieces, and get a feel for current endgame mechanics. Getting to 99 is not the issue, its getting to 99 and being remotely capable of completing anything worth doing at 99.