Is this route possible under the 144 hr visa:United Arab Emirates - Shanghai - United Arab Emirates?

Your itinerary is ineligible for any kind of visa free transit because countries A and C have to be different. You will have to obtain a Chinese visa in advance if you want to retain your itinerary or you can be a bit creative and introduce some other country to make your itinerary eligible.

For example, if you introduce Hong Kong, like this:

UAE - Shanghai - Hong Kong - UAE

Your itinerary becomes eligible for 144 hour visa free transit. Of course, it doesn't have to be Hong Kong... It can be also Taipei or Bangkok or some other city/country... Just play a bit with some different options and you will definitely find some affordable visa free transit eligible itinerary.

Thank you! You might want to clarify that on your page, as it mentions A & C have to be different to mainland China - but it doesn’t actually say whether A & C can (or cannot) be the same. Thanks!