The hour that disappears: rescheduling classes when the world changes its clocks

Every October, a student in Sydney logs in to class an hour early. She has not made a mistake. Her clocks moved forward on 4 October and ours in India did not, so the class is exactly where it always was on her calendar and no longer where it always was on ours.

In three weeks the same thing will happen in reverse with our students in London, and a week after that with our students in New York.

Anyone who teaches online across borders knows this feeling. Twice a year, daylight saving time quietly rearranges the timetable. Nobody sends a memo, and the cost turns up as a missed class, a confused parent or a student waiting alone in a video call. It is one of the least-discussed parts of international teaching, so here is why it is harder than it looks, and the system that finally made it manageable for us.

Why daylight saving time is a teacher’s problem

India does not observe daylight saving time. Neither do the UAE, Singapore, most of Africa or Queensland. Much of our student base does: the UK and Europe, the US and Canada, New Zealand and southern Australia.

The catch is that the countries that do observe it do not change on the same day, and they do not even change in the same direction. These are this academic year’s dates:

• 27 September 2026: New Zealand moves forward
• 4 October 2026: southern Australia moves forward
• 25 October 2026: the UK and Europe move back
• 1 November 2026: the US and Canada move back
• 14 March 2027: the US and Canada move forward
• 28 March 2027: the UK and Europe move forward
• 4 April 2027: Australia and New Zealand move back

That is seven dates. A teacher with students on three continents sees the weekly timetable shift seven times in one academic year. Because the northern and southern hemispheres move in opposite directions, October squeezes the day from both ends at once: Australian classes slide earlier, while European and American classes slide later.

What actually goes wrong

Here is the kind of collision that happens. Picture a teacher in India with two regular Monday students:

• A student in London at 3:30 pm. During British Summer Time, that is 8:00 pm in India.
• A student in Dubai at 7:30 pm. That is 9:00 pm in India all year round, because the UAE does not change its clocks.

On 25 October the UK falls back an hour, and the London class moves to 9:00 pm in India. Two students are now booked into the same slot, and nobody did anything wrong.

Collisions are the easy part, because at least you can see them. The harder problems are quieter.

The silent drift. Calendar apps anchor a recurring event to the time zone of whoever created it. If the teacher creates the class in Indian time, the teacher’s calendar stays put and the student’s moves, so a 5 pm class becomes 4 pm, which might be before the child is home from school. If the family created the invite, the opposite happens. Neither side notices until someone is waiting in an empty call.

The shoulder weeks. From 14 to 28 March 2027 the US will have changed and the UK will not. For those two weeks New York is four hours behind London instead of five. Any family whose relatives, schools or tutors are split across those regions gets confused, and so do their children.

Ambiguous labels. “EST” is strictly correct only in winter, because in summer New York is on EDT. “IST” can mean India, Ireland or Israel. And when a parent writes “see you at 6” on WhatsApp, whose 6 is it? Most rescheduling mistakes are not really daylight saving mistakes. They are mistakes in how the time was written down.

Exam season lands right after the spring change. IB and Cambridge exam sessions begin in late April and May, only weeks after the clocks move. A missed revision class in early April is not a minor inconvenience. It is time a student cannot get back.

Teacher fatigue. When every class shifts by an hour, a teacher’s carefully protected evening or early morning disappears. Classes that used to finish at 10 pm now finish at 11 pm, and teaching at 11 pm is not teaching at 8 pm.

The decision every teacher must make: who moves?

Every time the clocks change, someone’s hour has to move: the student’s or the teacher’s. There is no neutral option.

Our default is that the student keeps their local time. A child’s life runs on local time — school, football practice, dinner, bedtime. A Year 10 student in Manchester cannot easily rearrange their day, but a teacher can usually rearrange theirs with a week’s notice.

That default has limits. When moving with the student would push a class into a slot that is already taken, or into an hour too late for good teaching, we do not quietly absorb it. We offer the family two alternative slots, early and in writing.

What matters most is to make the decision once, write it down as a policy and tell families before it matters, not on the evening of the clash.

Our seven-step playbook

This is the system we now run every September and every February.

1. Put the change dates in the calendar at the start of the year. All seven go in as all-day events, each with a reminder two weeks before. Daylight saving should never be a surprise.

2. Anchor each student’s recurring class to the student’s time zone. When we create the recurring event, its time zone is set to the student’s city — Europe/London or America/New_York, for example. The calendar then shifts our view automatically, and the family’s time stays fixed.

3. Run a clash check two weeks out. Before each change, we look at the following week in Indian time for overlaps, classes that now run too late and gaps that have opened up. It takes about fifteen minutes and has saved many awkward apologies.

4. Message every affected family 10 to 14 days ahead, with both times written out. This is the template we use:

   Hello! A quick note: clocks in the UK go back on Sunday 25 October. Your daughter’s Monday Maths class stays at 3:30 pm London time, as usual. Nothing changes for you. (For our planning, that is now 9:00 pm in India.)

   Families mostly want to hear “nothing changes for you”. When something does need to change, they need to hear it early.

5. Write times with city names, never only abbreviations. “4:00 pm London / 9:30 pm Delhi” cannot be misread. “4 pm GMT” can, especially in a week when the UK is not actually on GMT.

6. Confirm the first class after each change personally. A short message on the morning of that class — “See you today at 4:00 pm your time!” — catches the last few mix-ups.

7. Give grace in the week of the change. If a student misses a class in the week the clocks moved, we do not treat it as a no-show. We reschedule it. Treating an honest time-zone mistake as the student’s fault damages trust far more than one rescheduled hour costs.

Teaching across time zones builds trust

We have come to see the twice-yearly shuffle as more than an administrative headache. It is one of the clearest signals of how seriously a teacher takes a family’s time.

Parents notice when you know their clocks are changing before they do. They notice when the reminder arrives early, gives their time first and tells them nothing will change. And they remember the evening they waited in an empty video call while their child grew anxious about a missed Physics class two weeks before the IB exams.

Students around the world live in different hours, so continuity has to be designed in. It does not happen by accident.

At TutorWyz, we teach Mathematics, Physics, Chemistry, Biology and English to students on every continent from India. We do not change our clocks, so we have learned to keep track of everyone else’s.