Customers who got in quick with 27-inch iMac pre-orders may receive their 27-inch iMac as early Thursday 13 December.

Some of the customers who ordered their new iMac on 30 November have received notifications alerting them to the fact that their orders have now shipped. See: How to install extra RAM memory in the new iMac and save on Apple's high prices

Apple had initially promised orders would arrive by 18 December, but according to a 9toMac report, some customers have an estimated arrival date of 13 December.

9to5Mac notes that the 27-inch iMacs are shipping from Shanghai, China, rather than Fremont in the US, as was the case with the 21-inch iMac. Some new iMacs were inscribed with Assembled in USA, leading to speculation as to where in the USA construction was taking place.

This speculation was further fuelled when Apple CEO Tim Cook last week revealed that the company would be manufacturing a line of its Macs in the US next year. Back in the 1990s, Apple manufactured its iMacs at its Elk Grove, California, campus before moving its assembly lines to China, but the recent announcement that Apple will be returning some of its Mac production to the US has ignited excitement at the campus once more. Fremont (Also in California) is 83 miles from Elk Grove. 

The 27-inch iMac has has been available for pre-order since 30 November, when Apple said it would ship the all-in-one desktop in one to two weeks. Days later, that grew to three to four weeks. Shipping of the 27-inch iMac is now listed as available to ship in January.

The smaller, 21-inch iMac started shipping at the end of. Apple had announced near November's end that the 27-inch iMac would start shipping in December, and while that may have been the case, it looks like supplies are too constrained for new orders.

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