The UK kept the Pound Sterling, miles, and pints when it joined the EU, so I don't see why they'd get rid of DST just because the continentals are.
Given we couldn't even be bothered to move to a timezone that EU other countries are on (Portugal aside), I can't see there being much appetite for change.
Now, if the EU Commission had said they were forbidding the removal of daylight saving, I think it would be a completely different story...
And -the republic of- Ireland! A "timezone" border to be added to the one already introduced by Brexit