As you are a regular customer at PCGS, if you let them know that you don't agree with the grade, they will review your coin for no charge and perhaps even cover the shipping costs. Right ?
If there is a labelling error, or you think the coin is overgraded, they will review it for free. However, this is just they got it wrong so they'll charge you again.
It's a service NGC calls "appearance review." Last year I sent them a coin that was labelled wrong, and they fixed it free. I also sent them 3 coins with PVC contamination, and they had them conserved and regraded. A few years ago, I also sent them a clearly overgraded 66FBL Franklin, and they agreed and regraded it 65FBL. I don't have pictures of that one anymore, unfortunately.