Yes, but GMT is always the same time. We just add on an hour for BST (dating back to the war, to get more hours of sunlight for farming.). This is GMT+1 or BST or Daylight Saving Time. Whichever. GMT+1 is currently what's on in the UK. Therefore, GMT is 1 hour behind current UK time, and so when the time goes back also 1 hour in the winter (things seem to get darker earlier), it will be GMT (*no +1 any more*).