You might be interested to know that Sky seem to have changed their policy on removing the Sky+ facility when you drop the subscription. I was on the phone to retentions at the weekend as I'm cancelling my package - we got talking about the Sky+ sub and I said the likes of BT/TalkTalk YouView allow you to continue recording if you drop the sub. The agent said, yes in response to this we've recently changed our policy to allow you to keep the Sky+ feature for no charge when you drop the subscription. However, it looks as though you have to call customer services to either request it to be added or state when you cancel your subscription that you want to keep the Sky+ feature. I don't think they will automatically add it to non-subscribers with a Sky+HD box. Also note that with respect to CatchupTV, you can only download BBC iPlayer content - I tested the other players and these don't work without subscription. For info, Sky applied the Sky+ feature to a FSFS card that was not used for subscription.
Presumably when you call Sky with your request, they will do their best to get you to become a subscriber again.
I also dropped an e-mail to customer relations who also confirmed that the policy had recently changed, however you must call customer services to request for the Sky+ feature to be added to your viewing card.
As ever with the call centre, policy changes don't always filter through to agents.