I don't think there were ever any plans for Frisco schools to attend, but UIL Region is October 20th so they definitely won't be attending.
I haven't worked on the field so I don't have any first hand knowledge, but I have heard from others that The Star is terrible for marching band setup, getting on and off the field, warming up, etc. Of course the rain last year during the Frisco ISD Marching Exhibition made everything worse. Wet uniforms, plumes, props, etc.