Daylight Saving Switch Week: What to Do When the Time Gap Moves by 1 Hour
US markets run on Eastern Time, so if you watch from Beijing time you first have to line up the clocks. Twice a year the clocks move by 1 hour: into daylight saving on the 2nd Sunday of March, back to standard time on the 1st Sunday of November. The switch day is a Sunday, so there is no trading that day — but from the Monday after, your open, no-new-position, and close times in Beijing all move by 1 hour. If you do not move your alarms, you will be 1 hour late or 1 hour early.
Which two days switch, and how the gap moves
US daylight saving starts at 2:00 a.m. on the 2nd Sunday of March and ends at 2:00 a.m. on the 1st Sunday of November; the dates change every year, so learn the rule, not the dates.
In 2026: daylight saving began March 8 and ended November 1; in 2027: it begins March 14 and ends November 7.
March switch: clocks jump forward 1 hour, standard time EST (UTC-5) becomes daylight time EDT (UTC-4), and the gap shrinks from 13 hours to 12.
November switch: clocks fall back 1 hour, daylight time EDT becomes standard time EST, and the gap goes back from 12 hours to 13.
How the Beijing-time table moves in the week after the switch
From the Monday after the March switch: the 9:30 a.m. open is 9:30 p.m. Beijing time (was 10:30 p.m.), 1 hour earlier.
From the Monday after the March switch: no new positions at 3:30 p.m. is 3:30 a.m. the next day Beijing time (was 4:30 a.m.), and the 4:00 p.m. close is 4:00 a.m. the next day (was 5:00 a.m.).
From the Monday after the November switch: the 9:30 a.m. open is 10:30 p.m. Beijing time (was 9:30 p.m.), 1 hour later.
From the Monday after the November switch: no new positions at 3:30 p.m. is 4:30 a.m. the next day Beijing time (was 3:30 a.m.), and the 4:00 p.m. close is 5:00 a.m. the next day (was 4:00 a.m.).
The easiest mistakes to make
The switch Sunday is not a trading day: the switch falls on a Sunday, when US markets are closed; the gap only really changes at Monday's open, so do not apply the new gap on Sunday.
Alarms still on the old table: on the Monday after the switch, an alarm set to the old time goes off 1 hour late (in March) or 1 hour early (in November) — move your alarms on the Sunday evening of the switch.
Moving the open but not the close: the open, the no-new-position cutoff, the flat reminder, and the close all move by 1 hour together; move only one and your exit will still be wrong.
The simulator's home-page countdown runs on Eastern Time and needs no conversion — when it says how many minutes are left, that is how many are left; do not check it against the old table.
How to practice the switch week in the simulator
On the Sunday evening of the switch, check once: the gap between the Eastern Time and Beijing time on the home page — 12 hours means daylight saving, 13 hours means standard time.
Move your alarms with the switch: after the March switch, move the pre-cutoff alarm from 4:25 a.m. to 3:25 a.m. and the pre-flat alarm from 4:50 a.m. to 3:50 a.m.; after the November switch, move them back.
On the first day after the switch, practice with just 1 long single-leg contract: run the full timeline from open to close, confirm your clock is right, and only then add size.
It is now standard time, a 13-hour gap; the next switch is Sunday, March 14, 2027, and from Monday, March 15, practice on the daylight-saving 12-hour table.
This simulator uses real CBOE option chains delayed about 15 minutes, starts with $10,000 in virtual funds, charges $0.65 per contract per side in fees, and shows P&L net of fees; short-sale margin is a simplified simulated rule at 20% of the strike, not a real broker margin. The simulator is for practicing orders, discipline, and review. It is not investment advice and promises no returns.