I assume that the D ONLY means DIXONS ONLY but I am guessing. Cannot mean dual fuel as the spec is electric/ceramic.
Cannot see them making these just for sale at DIXONS but I seem to recall that DIXONS and another large retailer [??] are identical companies [could be wrong] so perhaps it means that this model is not available at the 'other' retailer.
Sorry I can't help further.
Maybe someone on here can give you a definitive answer.
If you need to find a tradesperson to get your job done, please try our local search below,
or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Please select a service and enter a location to continue...
Are you a trade or supplier? You can create your listing free at DIYnot Local