Hamburg is 4 hours ahead of Montevideo
Best overlap: 8:00 AM to 2:00 PM in Montevideo is 12:00 PM to 6:00 PM in Hamburg.
Both offices are open during 8:00 AM to 2:00 PM Montevideo time, which is 12:00 PM to 6:00 PM in Hamburg. Hamburg is 4 hours ahead of Montevideo, and with 6 hours of overlap you can even run back-to-back calls without stepping outside business hours. Just remember Hamburg changes its clocks for daylight saving and Montevideo doesn't, so confirm the overlap whenever the seasons turn.