Converting a Time from a database to BST with PHP

So I’ve trying all sorts of combinations to get a date from my database (using WordPress) to display in British Summer Time and I cannot get anything to work.

Is there any simple solution that can take the date string and make sure that in Summer Time in the UK it’s an hour on from UTC time?

$classJson = $class->info;
$classJsonAsArray = json_decode($classJson, TRUE);

$classStartDate = strtotime($class->periodStart);
$classStartTime = date('H:i',$classStartDate);

So currently $class->periodStart returns: 2022-04-06 08:30:00

The time of that event should be 9.30am

All I need it to do is display the correct time, as at the moment, on the front end it displays as 8.30am.