According to the Canadian Government Citizenship and Immigration Website (won't let me post a URL).....
Who became a citizen under the new law
The law restores citizenship to people who:
became citizens when the first citizenship act took effect on January 1, 1947, including people born in Canada prior to 1947 and war brides. It also applies to other British subjects who had lived in Canada for at least five years before 1947, became citizens on January 1, 1947, and who then lost citizenship.
It also restores citizenship to people who:
were born in Canada or who became Canadian citizens on or after January 1, 1947, and who then lost their citizenship and
were born outside Canada, on or after January 1, 1947, in the first generation born abroad, to a Canadian citizen.
The law also gives citizenship to some people who have never been citizens. This includes people who:
were born outside Canada on or after January 1, 1947
are in the first generation born abroad and
were born to a Canadian citizen.