Just having a look at old MAN routes and came across this article from Summer 2009 regarding Air China. Seems the route has been in the planning for some time and had the traffic rights for daily A330 Beijing flights:
CAAC initial int?l route allocation for 2008 & 09 | Airline Route
Never knew the route got so far down the line.
Interesting thing about the article though is that of the 12 routes mentioned, Manchester and Warsaw are the only 2 Air China has never flown too. All the other routes have either operated historically or are due to start this summer like Washington and Vienna. Or in most cases they operate the routes currently and have done since the article was released in summer 2009.