Such a cool bro.
The SPF has the same standard on the rule book for depth as everyone. Most of the side judges at the meets are not professional judges, so yeah, at some of em you will get high squats.
The SPF meet I did had a lot of people red lighted for depth, including some I thought were good.
So moral of the story, make sure you go just deep enough for two white lights, and youre good.