The OP does not give the year in which his father was born, but considering that the OP was born in 1991, the father was almost certainly born before 1977. That being the case, the father's birth abroad would have had to be registered with Canadian authorities in order for him to have inherited Canadian citizenship from his father, the OP's grandfather. If it was not, then the OP's father was not a Canadian citizen until the changes to the Citizenship Act took effect on April 17, 2009. Although the father was made a citizen retroactive to his birth, this does not help the OP, because the limit on citizenship by descent to the first generation born abroad took effect at the same moment as did the retroactivity.
The OP's father had the ability to make a delayed registration of birth abroad (
http://www.cic.gc.ca/english/resources/tools/cit/proof/registration.asp), and thereby become a Canadian citizen, but that possibility expired in 2004. If he had done so [it sounds like that's what the uncle did], the OP would be a Canadian citizen now.