Yeas, I noticed something in that too especially since the mask was two pieces, a front and rear... I've googled a little more and found a different shape for the forward end.
I sanded the blue off. Didn't get it all though. No matter how much I sanded the blue dust would keep staining the white. Tried wet sanding too but that discolored the white too. Actually exposed some primer while sanding trying to get the blue gone. Finally called it good and sprayed the white again. Should be good for another masking tomorrow.
I cut a new mask tonight. Yep, with a different front shape. I have to go to El Paso tomorrow and I hope to swing by Grainger to pick up a can of Acryli-Quik Regal Blue. Not sure if it will be the color I'm looking for as the pics on the internet vary considerably so we'll just have to see.
-Bob