Mac Rumors has the report:
Following a September report stating that Apple may be working with Quanta Computer to develop a larger-sized iPad, Digitimes is now reporting that the Taiwanese-based manufacturer has landed the contract to mass-produce the tablet for the second half of 2014. Just last week, a report had claimed that the larger iPad was being targeted for an early 2014 launch.
The article also mentions that Quanta is expected to face difficulties when assembling the larger iPad because of its unique industrial design and assembly, which could also lead to constrained supplies:
Quanta is expected to encounter several challenges in terms of industrial design and assembly when making the large-size iPad. And since the size is not the mainstream specification, order volumes are expected to be limited, the sources said.
Leaving aside Digitimes’ (ahem) uneven reputation, that last bit doesn’t really pass the sniff test. Apple is hardly known to expand a product category just to fill a niche with low-volume sales.