Unknown, might see pre-orders mid/end September, but right now the clear objective is getting stock of MBA cards.
Also I quite like the plain and clean design on reference cards, both AMD and NVIDIA, plus the heat out the case is always good anyway, only ever an issue if the things sound like a Dyson at full tilt, though these latest cards from NV/AMD with blowers are tolerable, especially if you setup custom fan curves.
I'm sure I'm not alone when I say that I've had AMD blowers, and never again. AIB cards just have better, quieter cooling, and as long as you've got decent cooling in your case, it's far better than a little slot in the back of the case to expel heat.
Most people are going to want a single card, so without multiple cards (not that AMD seem to be supporting Crossfire anymore), there's just no upside to the blower design.