There were special programs at that time for Cuban refugees so he was not necessarily held to the 4 year limit. I read today that he became a Canadian citizen in 1968.
I should really stop reading UP threads. The above info is very interesting. If he became a Canadian citizen in 1968, could Cruz' mother have gotten some kind of expedited citizenhip too? I have read a direct quote, fwiw, from Cruz Sr but I cannot find it now, wherein he said that he and his wife BOTH became Canadian citizenship.
According to the Cruz campaign he became a Canadian citizen in 1973
http://www.breitbart.com/big-government/2016/01/08/ted-cruz-parents-canada-voters-list/
Cruz Sr. was not a Cuban refugee but a permanent legal resident of the US. Even if such a program existed, it would not have made Cruz sr. a Canadian citizen immediately - more likely he was given permanent legal status which could eventually lead to citizenship