Reykjavik is 5.5 hours behind Colombo
Best overlap: 2:00 PM to 6:00 PM in Colombo is 8:30 AM to 12:30 PM in Reykjavik.
Aim for 2:00 PM to 6:00 PM Colombo time — that's 8:30 AM to 12:30 PM over in Reykjavik. Reykjavik is 5.5 hours behind Colombo, which gives you a solid 4-hour window. Book earlier in it and neither side is rushing.