Finals Eligibility for players

This applies for all divisions across the board and I have heard several different versions of this so want to put it out there with finals coming up!
How many games does a player have to play to be eligible to play finals for that team?
E.g. If a player is going between a's and b's all year, what ratio of games does he need to have played to play in the lower grade?
50/50? 70/30?
I am aware that if both A's and B's are in the finals than it doesn't matter, but what if the A's are not playing finals?
Also is there any loop holes or other rules to do with the last half of the season or playing the final 3 games in the lower grade etc?
How many games does a player have to play to be eligible to play finals for that team?
E.g. If a player is going between a's and b's all year, what ratio of games does he need to have played to play in the lower grade?
50/50? 70/30?
I am aware that if both A's and B's are in the finals than it doesn't matter, but what if the A's are not playing finals?
Also is there any loop holes or other rules to do with the last half of the season or playing the final 3 games in the lower grade etc?