Millions of Canadians set their clocks back an hour for winter, while residents of several provinces and regions do not. British Columbia recently adopted daylight saving time as its standard time, and Alberta, Manitoba and parts of western Ontario are also entering winter without switching back to winter time.

Experts said avoiding the twice-yearly clock change could be beneficial but criticized the choice of permanent daylight saving time, warning that darker mornings could disrupt sleep and affect adolescents and road safety. Quebec’s premier wants to end the clock changes and plans to consult experts before deciding between daylight saving and standard time. Ontario will only end the changes if neighboring regions, including Manitoba, Quebec and New York State, do the same.