I see they handle Daylight saving, albeit they flag that entire week as the change from what I can see for the UK which has a change from GMT to BST (which they call UST+1) on the 28th - yet whole week gets labelled that in which it changes.
Personally I'll be glad when we do away with such daylight saving TZ changes.
It doesn't seem to handle DST properly at all. If I set the date to the 27th, it shows London on the 28th being GMT, if I set it to the 28th it shows London on the 27th being BST. Both wrong. It should instead show the 28th as being only a 23 hour day and the 31st October being a 25 hour day.