The return visit to the UK was in 1926, so that was before the 1927 trip back to Canada. Presumably, she went to Scotland for a visit without Thomas and then came back to Canada.
I also found these:
SS Montclare sailing 15 Feb. 1924, then C.P.R. railway to Calgary -
Minnie Dickson, age 30, married to Thomas Dickson, born Coldstream, Scottish, British citizen, Protestant, going to Canada "to make my home", never lived in Canada before, in possession of $600, passage paid by husband, going to 2833 26th A St., Calgary, Alberta, nearest relative - mother Mrs. Curran, Duke Street, Coldstream
Thomas Dickson, age 42, married, accompanied by wife Mrs. T. Dickson, intended occupation - farming, born Coldstream, Scottish, British citizen, Protestant, going to Canada for farming, going to 2833 -26A Street West., Calgary, Alberta, previously entered Canada at St. John in March 1911, previously departed Canada on holiday from Quebec in Nov. 1923, in possession of $600, passage paid by self, nearest relative - mother Mrs. Dickson, 16 Leet Street, Coldstream
I'll move this over to the Canada board and maybe they can help with any other Canada information.