Best overlap: 8:00 AM to 11:00 AM in Helsinki is 3:00 PM to 6:00 PM in Brisbane.
Shoot for 8:00 AM to 11:00 AM in Helsinki; your Brisbane colleagues will see that as 3:00 PM to 6:00 PM. A 3-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: Helsinki observes daylight saving, Brisbane 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Helsinki Europe/Helsinki | ||||||||||||||||||||||||
Brisbane Australia/Brisbane |
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. -