CBS All Access App wants a TV Box upgrade to work ?

When I'm in the streaming apps and click to set up the new CBS All Access app I keep getting a pop up asking if I want to upgrade my equipment.  If I choose no, I'm kicked out of the App.  So apparently I won't be able to use the CBS All Access App unless I get a new TV Box ?  All the other streaming Apps are working, e.g., Prime and Netflix.  I currently subscribe to CBS All Access and cast it with chromecast.  I really don't want to go thru the hassle of having to have Comcast come and set up a new box and take back the old one just for this app.  My current TV box is:   MX011ANM