Andrew Smith, one of my regular link-tos, is shocked and saddened by the lack of attention given in Canad to the 80th anniversary of the passage of the Statute of Westminster in 1931 as it "marked the effective end of Canada's subordination to Britain." (Weirdly, the Canadian Navy marked the event by flying the Union Jack. Guys....) Andrew thinks it is a sign of Canadians' constitution ignorance.
But Janet Ajzenstat, almost simultaneously, puts forth 1848 as the significant moment that "sever[ed] the colonies' formal connection with the mother country." By that reading, the 1931 Statute would dwindle to a formality -- the Empire's belated recognition of what had transpired a century earlier.
I lean to the Ajzenstat reading, myself. But can't help being pleased with the stuff you can find on what CanHist blogs we have out there.