Calgary is 16 hours behind Melbourne
Best overlap: 8:00 AM to 10:00 AM in Melbourne is 4:00 PM to 6:00 PM in Calgary.
The overlap falls at 8:00 AM to 10:00 AM in Melbourne, or 4:00 PM to 6:00 PM if you're in Calgary. The window is short at 2 hours, so keep meetings tight and anchored to 8:00 AM in Melbourne (4:00 PM in Calgary). The two cities aren't on the same date during this window — Calgary runs the previous day from Melbourne.