At 01:00 GMT on Sunday 31st Mar 2019 clocks will be advanced 1 hour to 02:00 BST, time zone Alpha. (We don’t do UTC on this site.)
Clocks will remain on Alpha time until 01:00 on Sunday 27th October 2019 when they will be retarded to GMT time zone Zulu.
If you need to check your timepiece have a look HERE for a GMT clock.