seems reasonable
This does seem reasonable. It will stop these companies from being accused of selling people products that won't work. Also it means that they will have time to clear stocks of analogue devices well before the change over. You will still be able to get analogue devices from other suppliers just not this group so it a non issue really.
The biggest problem is going to be the piss poor reception for freeview devices in many areas. This isn't the fault of the retailers though. Might be a good time to set up a company installing new TV aerials though...