I was rejigging the grades every 1-2 weeks for two thirds of the season (plus obviously everyone plays in our finals playoffs which have to have to be done week to week). This kept the comp very even but obviously has downsides.

Anyway the point is taken (a couple of others have said the same thing) so we will change it so regrade only in weeks 5 and 8 and then set the grades in stone. This will reduce the issue substantially but I can eliminate it completely as I don´t want to end up like other comps where 20-30% of teams aren´t competitive in the grade they are in and end up discouraged (and often being no shows).