There is no standard 8-to-6 overlap. Someone joins early or late.
Coordinating Perth and Philadelphia is tricky: 12 hours of separation means their standard hours don't intersect. Async-first is your friend here. Reserve real-time meetings for the rare occasions someone can log on before or after hours. Just remember Philadelphia changes its clocks for daylight saving and Perth doesn't, so confirm the overlap whenever the seasons turn.
| 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Perth Australia/Perth | ||||||||||||||||||||||||
Philadelphia America/New York |
The US to Australia gap runs 14 to 19 hours depending on the month, and someone is always in tomorrow. Exact overlap windows for every US coast, the double-DST trap, and a rotation rule that keeps it fair. -