You ought to read the smal print on the manual and box that the receiver came in, it will be extremely small in BSKYBs case
In advertising and promotions a company is entitled to deviate from the truth to some extent, the same has been true for a lot os manufacturers and broadcasters (anyone who has been in this industry woill know of the last Dolby/Wegener/Panda scam with Echostar. It was plastered all over their adverts as Wegener, but the final product and spec was only Panda compatible - something to do with the payment of royalties.
With Sky if theyspoke the truth you would have
1) Amstrads that work for more than a year 2) Someone with an ounce of grey matter on the other end of the helpline 3) VCR ports on the receivers that allow loopthrough 4) Remotes that dont run the batteries flat each month 5) Original viewers that paid for the box, get a full refund 6) Authorised Sky Agents carrying out a basic install for nothing, rather than make lame excuses to charge for anything that looks more complicated than a dish on the other side of a breezeblock wall to the TV, next to a telephone socket. 6) Uninterrupted reception at all times, in all weathers, with the standard dish 7) Nobody complaining