As you know Breaking Dawn will be filmed in 2 parts, the first part being shot in Louisiana and the second being shot in Vancouver.
RobertPattinsonNews noticed the following in the fine print to the auction of Stand Up to Cancer for the Breaking Dawn set:
The experience will take place between February 1, 2011, and the end of March 2011, when the crew is filming on the Vancouver set. The specific date within this range will be determined based on the film’s production schedule and winning bidder’s availability.
Therefore we can safely assume that filming will be taking place in Vancouver between February and March 2011.
You can check out the auction here.
Thinking of Rob 
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