More information is filtering in on a Tau Mercenary codex supplement, and even a date is showing up. This would put us out until early next year, and possibly with a few models. Even the Biel-Tan are mentioned, which would assume that something on them is being worked on.
Please remember that these are rumors, with some speculation based off what was seen near the bottom.
via Stickmonkey on Faeit 212
I have a little more on the Tau mercs supplement.
First, I was told this wasnt planned be out til Q1.
Second, I was told that either this or one of the eldar supplements would be the first with a model wave to go along with it. I wasnt told which models or which eldar supplement.
warning: what follows is my speculation
My best guesses are a plastic pack kroot hq, which I saw in design before. This would be a slightly bigger kroot than the current troops. Had a tau rifle, not a kroot gun. A bit more armor than a standard kroot. Standing on a rock in a "crossing the Delaware" pose. Caveat that this was still in CAD, lots can change, and it was last fall.
Also a vespid plastic kit thats been ready for a while.
My eldar guess would be the first round of the plastic aspects with beil-tan.
When the tau dex was released I went back to my sources about the allied races not getting support after seeing so much studio work on them, and this was eventually what I was told.