Late News: I did get a chance to speak with Autoglym just before publishing this and I was able to learn that this is a stand-alone, one-step product. It is not designed to be used with Super Resin Polish or topped with Extra Gloss Protection.
http://www.properautocare.com/auuldesh.html
Since UDS is a substitute to the SRP, it is logical that they cannot be used side by side, but what about EGP? Does anyone know the reason?