Seems the Cant Z.506B were initially coded 73-1 to 73-4
http://www.aviationcorner.net/galler...t_type_id=1951
On the 15th of July 1942 73-2 (by then renumbered as 53-2)
http://www.network54.com/Forum/39472...s+extranjeros-
comandante Ignacio Ansaldo Vejarano, Z.506B, 15 JUL 1942,
http://fotosantiguasdemallorca.blogs...ollensa-y.html
https://m.facebook.com/notes/aviador...3769053009246/
Sunderland O/202, P/O Lauwrence, 15 JUL 1942 off Majorca (Short Sunderland in WWII, Andrew Hendrie, p.62.)
John Thornett LAWRENCE (104428)
http://www.bbm.org.uk/LawrenceJT.htm
When a date is given, it's always the 15 JUL...