Reykjavik is 8 hours behind Hong Kong
Best overlap: 4:00 PM to 6:00 PM in Hong Kong is 8:00 AM to 10:00 AM in Reykjavik.
Both offices are open during 4:00 PM to 6:00 PM Hong Kong time, which is 8:00 AM to 10:00 AM in Reykjavik. Just 2 hours of shared hours means there's little margin — set 4:00 PM in Hong Kong (8:00 AM in Reykjavik) and start promptly.