I didn't see anything Transformers specific in Walmart or TRU boxing day flyers, but just in case anything else may be of interest. Doesn't mean that Transformers won't go on sale, just not advertised so best to check online for clearance or your local store if you're already there.
Walmart:
http://flyers.smartcanucks.ca/canada...2015/thumbnail
Toys R Us:
http://www.saveland.ca/ToysRUs/flyers/18409/