What was likely said next? Dialog:
Speaker A) What was the first wartime use of the M15-class monitor?
Speaker B) The remainder served in the Mediterranean from 1915, with "M23" joining the Dover Patrol in June 1917 and "M21" in October 1917.
Speaker A) What happened in the Second World War?
Speaker B) As part of the intervention into the Russian civil war "M23", "M24", "M25" and "M27" served in support of British and White Russian forces in the White Sea in May to September 1919.
Speaker A) Are there any other interesting aspects about this article?
Speaker B) 
"M22" was converted to a minelayer in 1920, whilst "M23" became a drill ship, surviving until 1959.