Apple's upstream supply chain is expected to start supplying components for the upcoming 12.9-inch iPad in late-September and the device is expected to become available in the market after mid-November; however, Apple is rather cautious about placing related orders and the initial shipment volume is much lower than most market watchers' expectations, according to sources from the upstream supply chain.

The tablet will be manufactured by Foxconn Electronics (Hon Hai Precision Industry), the sources noted.

With demand for tablets weakening a lot faster than expected, sales of iPad, white-box and brand tablets have all been seriously impacted recently. Strong popularity of smartphones with 5-inch and above displays plus the fact that tablet is lacking new innovative applications are also major factors seriously undermining tablet sales.

In fact, most tablet players may see difficulties achieving their shipment goals for 2015 or making profits from the product line. Some white-box players are relying on Intel's subsidies to keep their operation in the tablet market, the sources said.