Best overlap: 8:00 AM to 2:00 PM in London is 12:30 PM to 6:30 PM in Kolkata.
Book within 8:00 AM to 2:00 PM London time (12:30 PM to 6:30 PM in Kolkata) and both teams will be at work. That's a roomy 6 hours of common time each day, so finding a slot that suits everyone is rarely a problem. For part of the year the maths changes: London 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
London Europe/London | ||||||||||||||||||||||||
Kolkata Asia/Kolkata |
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