Daylight saving - best approach

I've built my own scheduler in node-red for controlling stuff around the house.
The basic data structure is an array of entries like:
[actionID, time, recurrence, parameters]
[10, 1648395000000, 86400000,{which:"fish", state:"on"}]
Above should turn on the fish tank light at 16:30 every day.
The time is stored as MS since 1-1-1970 00:00:00 UTC.
Today the clocks here in London went forward to summer time; but all my events need to respect local time.
I can fudge the schedule by adding 60000 onto all the times (then taking it off in 6 months time); but I'd like to do the job properly. So if you schedule something at 22:00 it happens at 22:00 all year long.
Any suggestions of how best to implement this?

You can use
const offset = new Date().getTimezoneOffset()
Which will give you the current timezone offset in minutes. You can use that to offset the time you are comparing against.

I found using "hh:mm", not timestamps much easier to deal with when constructing daily schedules.
[ {"id":0,"to":"02:00","temp":19.5}, {"id":1,"to":"10:00","temp":20.5}, ...] //id not essential if array is always sorted

function getTemp(sched) {
    //return the scheduled temp for this time of day
    const now = moment();
    let test = moment();
    return sched.find(el => {
        const hhmm =":");
        //change midnight this morning (00:00) to midnight tonight (23:59:59)
        if ( == "00:00") test.hour(23).minute(59).second(59);
        else test.hour(hhmm[0]).minute(hhmm[1]);
        return now.isSameOrBefore(test, "second");

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