as per CHC-London avg time is 9-12 months and time counts from the day they received docs... (4 exampl) if you've sent your docs in april and recvd AOR in aug than already 4 months are gone so they'll complete and process case in 6-8 months time, now i ve seen after placing cap of 20,000 canadian govt is forcing VOs to expdite process and clear backlog. Base on recent available update 80% cases @ London were finalized in 11 months time (july,09 - june,10) and hopefully this will b reduced Inshallah for 2010/2011..
http://www.canadainternational.gc.ca/united_kingdom-royaume_uni/visas/processing-traitement.aspx
(Isb and London have processed 80% FSW cases in same time)
http://www.cic.gc.ca/english/information/times/international/02b-skilled-fed.asp