Best overlap: 8:30 AM to 12:30 PM in Edinburgh is 2:00 PM to 6:00 PM in Kolkata.
Plan around 8:30 AM to 12:30 PM in Edinburgh, which is 2:00 PM to 6:00 PM in Kolkata, to catch everyone during office hours. A 4-hour overlap gives you a workable daily window; aim for earlier in it to avoid clipping the end of someone's day. For part of the year the maths changes: Edinburgh observes daylight saving, Kolkata does not, shifting the overlap by an hour.
| Local time | 12am | 1am | 2am | 3am | 4am | 5am | 6am | 7am | 8am | 9am | 10am | 11am | 12pm | 1pm | 2pm | 3pm | 4pm | 5pm | 6pm | 7pm | 8pm | 9pm | 10pm | 11pm |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Edinburgh Europe/London | ||||||||||||||||||||||||
Kolkata Asia/Kolkata |
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