I clearly see your point of view in terms of the opening wording of section 50, which says that every House of Commons shall continue for five years; however, had the government wished to change section 50, it would have been open to the government to do so under section 44 of the Constitution Act, 1982.
Je comprends parfaitement votre interprétation de l'article 50, qui dispose que chaque législature durera cinq ans mais, si le gouvernement avait voulu modifier l'article 50, il aurait eu la possibilité de le faire au moyen de l'article 44 de la Loi constitutionnelle de 1982.