question on bylaws

[lyrica9]

i know its kind of odd, but i was wondering if there is any standard/set guideline/rule on when bylaw revisions go into effect. i checked our bylaws and the only provision remotely close to this was when revisions had to be submitted to the province director.

i ask because earlier i got an email from our MEVP saying that I didnt make grades, which was news to me.
Aparently we changed the requirement when we did bylaw revisions.
my question arises because, at the beginning of the spring semester our GPA requirement was one thing, and we revised it in the middle of the semester, so theorhetically it shouldn't go into effect until the end of this semester to be fair, correct?

basically im mad because at the beginning of last semester i was aware of one standard, and i dont think its right for it to change halfway through, when classes are halfway over.