Master copy being saved over after signing

I have a master copy of a form my clients are to fill out and then sign, but when it is signed the form is saved over and then I have no master file. If I make it read only it fails to save, I have tried to give it a path to save as so it wont write over my master file but the best outcome is if the master file is not read only and upon signing it will save over the master AND make a save file where I want it to. I have a signature pad and I used the following java script when the form is signed:

lcbSaveAs(this, "/X/000 - Onboarding/" + this.getField("FirstName").valueAsString + " " +this.getField("LastName").valueAsString + " Application.pdf");

I also have the trusted function in the folder level javascript:

var lcbSaveAs = app.trustedFunction( function (vDoc, vPath) {

  app.beginPriv();

  vDoc.saveAs({cPath: vPath});

  app.endPriv();

});