Sherlock mentions a bar fight that occurred on August 23, 2009 involving a hockey game between the Canadiens and Rangers. August is the off-season for the NHL, which usually runs from October to June.
In the flashback from January 2014, Jack Brunelle tells Watson that his son was attacked 18 months prior, which would be sometime around July 2012. In the flashback from February 2016 however, he states the attack happened in January 2012. Considering he is attempting to hire Watson and Holmes to investigate, it is unusual that Mr. Brunelle's timeline would be inaccurate by six months, especially given the statute of limitations challenge he presented.
Marcus said the trucks in that drone surveillance video could haul up to 80,000 pounds. However Sherlock identifies them as Kenworth T440's, which is a medium-duty truck and is rated to haul a maximum of only 68,000 pounds.
It is highly unlikely that Joan, a trained physician would ignore a bleeding head wound for 16 hours without offering any aid at all.