Wellington is 13 hours ahead of Reykjavik
There is no standard 8-to-6 overlap. Someone joins early or late.
Wellington is 13 hours ahead of Reykjavik, which is far enough that a normal 9-to-5 in one city never reaches the other's working hours. One practical option: Reykjavik dials in early while it's still late afternoon or evening in Wellington. Finally, Wellington observes daylight saving and Reykjavik doesn't, so this window shifts by an hour for part of the year — recheck it each spring and autumn.