Pretty sure I read it somewhere that non-agression pacts were 2 years in this version. May be wrong about that. I know I tried to attack after making one and was told I couldn't do it until ... and that was 2 years from the time I made it. Then again, could have been one of those late nighters when you start hallucinating a little.
I'm sure one of the all-knowing members will correct me if I am wrong.