Helsinki is 6.5 hours behind Adelaide
Best overlap: 2:30 PM to 6:30 PM in Adelaide is 8:00 AM to 12:00 PM in Helsinki.
Your window to reach both cities is 2:30 PM to 6:30 PM in Adelaide, which converts to 8:00 AM to 12:00 PM in Helsinki. With about 4 hours of overlap, there's comfortable room for a daily stand-up — 2:30 PM in Adelaide / 8:00 AM in Helsinki works well.