Pair friction
low seasonal drift
São Paulo and London mostly keep a predictable gap, but there are short windows around the listed transitions when recurring meetings move by one hour.
Weekly digest
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DST pair drift
São Paulo (America/Sao_Paulo) and London (Europe/London) currently have a -4h difference. Across the next year, that gap takes 2 distinct values due to 2 DST transitions.
Last updated recently. DST-pair drift is calculated at render time from IANA timezone rules. It is meant for scheduling and planning, not for legal compliance or exchange-calendar decisions.
Live values rendered at Jun 8, 1:10 PM UTC.
Current gap
-4h
this week
Distinct gaps / year
2
how many values it takes
DST transitions
2
next 52 weeks
Stable run
22-30 wks
min–max consecutive
Pair friction
low seasonal drift
São Paulo and London mostly keep a predictable gap, but there are short windows around the listed transitions when recurring meetings move by one hour.
Longest stable window
22 weeks at -3h
From week of 2026-10-26 through 2027-03-22.
First drift warning
Week of 2026-10-26
The sampled gap changes to -3h in that week.
DST pair evidence
Practical use cases
Trust boundaries
Official policy sources
The weekly drift table is generated from deployed IANA timezone data. When a government changes daylight-saving law, use the official source for the jurisdiction and wait for the updated timezone database/runtime to land before trusting future weeks.
Used for exact UTC offsets, transition instants, and abbreviation changes in both zones. This is the machine-readable layer the app can calculate from.
Check IANA Time Zone DatabaseAmerica/Sao_Paulo
Brazil suspended daylight saving in 2019; describe the current IANA/app state, not a promise that policy can never return.
Check Brazil Ministry of Mines and EnergyEurope/London
GOV.UK publishes the public UK clock-change rule; IANA supplies the exact UTC instants used by the page.
Check GOV.UK clock changesRecurring-time examples
Use these examples when a recurring meeting, launch, class, livestream, or support shift is anchored to one city. When the gap changes, the receiving city sees the same fixed local time move by the amount shown in the drift table.
9:00 AM in São Paulo
5:00 PM in São Paulo
9:00 AM in London
5:00 PM in London
Transition-side read
São Paulo changes 0 times and London changes 2 times in the next sampled year. If one side changes before the other, check recurring calendar invites during the gap week instead of assuming the old local time still works.
Best stable-window strategy
The longest sampled run is 22 weeks at -3h. For seasonal campaigns, schedule the most fragile cross-timezone work inside that run when possible.
Reference fields include both IANA zones, the current gap, distinct gap values, transition counts, stable-window length, first drift week, transition-side counts, and anchored-time examples.
| Week of | São Paulo | London | Gap |
|---|---|---|---|
| 2026-06-15 | GMT-3 | GMT+1 | -4h |
| 2026-06-22 | GMT-3 | GMT+1 | -4h |
| 2026-06-29 | GMT-3 | GMT+1 | -4h |
| 2026-07-06 | GMT-3 | GMT+1 | -4h |
| 2026-07-13 | GMT-3 | GMT+1 | -4h |
| 2026-07-20 | GMT-3 | GMT+1 | -4h |
| 2026-07-27 | GMT-3 | GMT+1 | -4h |
| 2026-08-03 | GMT-3 | GMT+1 | -4h |
| 2026-08-10 | GMT-3 | GMT+1 | -4h |
| 2026-08-17 | GMT-3 | GMT+1 | -4h |
| 2026-08-24 | GMT-3 | GMT+1 | -4h |
| 2026-08-31 | GMT-3 | GMT+1 | -4h |
| 2026-09-07 | GMT-3 | GMT+1 | -4h |
| 2026-09-14 | GMT-3 | GMT+1 | -4h |
| 2026-09-21 | GMT-3 | GMT+1 | -4h |
| 2026-09-28 | GMT-3 | GMT+1 | -4h |
| 2026-10-05 | GMT-3 | GMT+1 | -4h |
| 2026-10-12 | GMT-3 | GMT+1 | -4h |
| 2026-10-19 | GMT-3 | GMT+1 | -4h |
| 2026-10-26 | GMT-3 | GMT | -3h |
| 2026-11-02 | GMT-3 | GMT | -3h |
| 2026-11-09 | GMT-3 | GMT | -3h |
| 2026-11-16 | GMT-3 | GMT | -3h |
| 2026-11-23 | GMT-3 | GMT | -3h |
| 2026-11-30 | GMT-3 | GMT | -3h |
| 2026-12-07 | GMT-3 | GMT | -3h |
| 2026-12-14 | GMT-3 | GMT | -3h |
| 2026-12-21 | GMT-3 | GMT | -3h |
| 2026-12-28 | GMT-3 | GMT | -3h |
| 2027-01-04 | GMT-3 | GMT | -3h |
| 2027-01-11 | GMT-3 | GMT | -3h |
| 2027-01-18 | GMT-3 | GMT | -3h |
| 2027-01-25 | GMT-3 | GMT | -3h |
| 2027-02-01 | GMT-3 | GMT | -3h |
| 2027-02-08 | GMT-3 | GMT | -3h |
| 2027-02-15 | GMT-3 | GMT | -3h |
| 2027-02-22 | GMT-3 | GMT | -3h |
| 2027-03-01 | GMT-3 | GMT | -3h |
| 2027-03-08 | GMT-3 | GMT | -3h |
| 2027-03-15 | GMT-3 | GMT | -3h |
| 2027-03-22 | GMT-3 | GMT | -3h |
| 2027-03-29 | GMT-3 | GMT+1 | -4h |
| 2027-04-05 | GMT-3 | GMT+1 | -4h |
| 2027-04-12 | GMT-3 | GMT+1 | -4h |
| 2027-04-19 | GMT-3 | GMT+1 | -4h |
| 2027-04-26 | GMT-3 | GMT+1 | -4h |
| 2027-05-03 | GMT-3 | GMT+1 | -4h |
| 2027-05-10 | GMT-3 | GMT+1 | -4h |
| 2027-05-17 | GMT-3 | GMT+1 | -4h |
| 2027-05-24 | GMT-3 | GMT+1 | -4h |
| 2027-05-31 | GMT-3 | GMT+1 | -4h |
| 2027-06-07 | GMT-3 | GMT+1 | -4h |