Canadian grandparents and father, but father immigrated to the US. Am I Canadian by descent?

[Ruken]

Hello! I guess I have sort of a complex case. My father left Canada for the U.S. before 1977. I'm unsure of when (or if) he became a U.S. citizen.
My understanding is if he acquired the citizenship of another country, he ceased to be a Canadian as dual citizenship was not recognized before 1977. Has this since been reversed by the 1977, 2005, 2009, or 2015 amendments to the Citizenship Act? Would I still be Canadian by descent through him or my grandparents? I was born in 1988.

The 'am I a Canadian' tool states I'm probably Canadian.

 

[hawk39]

With the exception of officially applying for and renouncing their Canadian citizenship or British subject status, or having it revoked due to acquiring it by fraud, any Canadian citizenship lost because of previous legislations (such as acquiring the citizenship of another country before 1977) was restored with the 2009 and 2015 Acts. The Acts also gave citizenship by descent to any foreign-born children they had during the time they were not Canadian citizens. In your case, you would derive citizenship by descent from your father, provided that he is not a citizen by descent himself.

 

[Ruken]

With the exception of officially applying for and renouncing their Canadian citizenship or British subject status, or having it revoked due to acquiring it by fraud, any Canadian citizenship lost because of previous legislations (such as acquiring the citizenship of another country before 1977) was restored with the 2009 and 2015 Acts. The Acts also gave citizenship by descent to any foreign-born children they had during the time they were not Canadian citizens. In your case, you would derive citizenship by descent from your father, provided that he is not a citizen by descent himself.

Thank you for your kind and informative reply!