The Arnold Hague database of CW convoys: The CW series ran from Southend to Yarmouth, Falmouth and St. Helens from July 1940 until May 1944. There was an additional American CW convoy that ran from Cristobal to Key West and Guantanamo, escorting vessels entering the Atlantic from the Panama Canal.
Note that the following convoys were cancelled.
CW.13
CW.84
CW.207
CW.270
CW STATUS
Convoys
272
Ship Entries
1,417
Escort Duties
210