Complex sentence: The "Evstafi" class, commissioned in 1910 ceased carrying the weapon but they were later fitted to patrol vessels and river craft during World War I and at least 62 weapons were converted to anti-aircraft guns by 1917.
Split into simpler sentences: The "Evstafi" class, commissioned in 1910 ceased carrying the weapon. However, they were subsequently fitted to patrol vessels and river craft during World War I, and at least 62 weapons were converted to anti-aircraft guns by 1917.