In reply to a post by MCM:

Isn't this all a bit like gas and electricity where the customer deals with their supplier rather than Transco and the other transmission companies that actually deliver the gas or electricity?

Yes, though in the latter case the quality of the product is exactly the same regardless of the chosen supplier, perhaps excepting smart meters. Also if you have a fault you have to complain to the actual supplier who may even pay compensation if you are cut off for a long time (48 hours in my case). The government now wants to interfere with the electricity market, which may mean that suppliers won't offer such good deals partly to attract new customers and partly to stop existing customers from leaving.

INFL has a separate company See The Light as their retail offering.

Presumably in much the same way as BT have BT retail. I wonder whether IFNL also have a wholesale arm comparable to BT Wholesale that supplies DirectSave, SeeTheLight etc or whether they simply cut out the middleman.