Just to confirm the previous answer:
Going back many years, it used to be the case that the date for the UK switch from BST to GMT (or vice versa) would be a week or two different from the changes in CET. (This meant that, for a week or two, the time difference between the UK and continental Europe would either be 2 hours or nil). This used to make ferry timetables almost impossible to read!! The situation nowadays is that the UK switch the CET changeover so that the time difference between the UK and (the nearer parts of) continental Europe is always 1 hour.
Chris