The current text says, Training with the sages and merchants of New Tanaan gives adventurers the chance to hone their crafting skills. This passive ability allows you to raise 1 additional standard tradeskill (Baking, Blacksmithing, Brewing, Fletching, Jewelcraft, Pottery, or Tailoring) from its initial Specialization cap of 200 up to 250. It should be 200 to 300, as far as I know this is how the AA actually works.
It was actually marked as a confirmed bug in 2019.... Just never fixed https://forums.daybreakgames.com/eq/index.php?threads/new-tanaan-crafting-mastery-aa.260556/
