Original sentence: Due for go on sale in 2011-12.It is thought to overtake the MK5 and the Ford Focus on sales.It will also be the platform for the new `green` plug-in series hybrid vehicles  "Ampria and Volt".It will be hitting the showrooms Dec 09.The MK 6 is due to come on-line at Vauxhall Ellsemere Port Plant Sept09
Edited sentence: It will be used as a platform for the new 'green' plug-in series of hybrid vehicles, alongside the American Chevrolet Ampria and Chevrolet Volt variants, which a due for a 2011/12 sale.The MK 6 is due to start manufacture at Vauxhall's Ellsemere Port Plant in September 2009, with the plan of appearing in showrooms in December 2009