Assuming you're talking about the Region 2 release, each episode is approximately 28 minutes long, which would indicate they're complete (half hour programmes on the BBC are never exactly 30 minutes in length - there are allowances for continuity announcers, trailers for other shows, etc).
Memory can play all sorts of tricks on us. I've seen people complaining about scenes that they thought had been cut from TV showings of 2001 for instance, when what they vivdly remembered seeing was actually an episode from the book.