Given Acer's belief that a tablet competition will spark at some point during the summer, it makes sense that it would already reserve production capacity with assembly companies.
Compal is a maker of white-box devices, meaning that it assembles devices according to blueprints provided by brand vendors, who later add their logos and labels to them.
According to Digitimes, Acer has placed orders there for the manufacture of a low-cost 10-inch tablet model.
Wistron was supposed to get the orders, but Compal won Acer over, though it didn't also get the 7.9-inch ones (Iconia A1-810).
On that note, the unnamed 10-inch model isn't the only device that Compal is making for Acer. The latter has also tasked it with the $150 / €150 Iconia B1 launched in 4Q12.