V1's and V2's, Bermondsey and Rotherhithe

Stainer Street Railway Arch, February 1941.

Railway arches were a popular place of shelter, but were more dangerous than they appeared to be. This picture shows rescuers searching the rubble at the railway arch at Stainer Street near London Bridge. The arch was destroyed in a raid on 17 February 1941 and more than 60 people were killed.

Stainer Street Arch Blue Plaque
 
Notice the date 17th February 1940? Surely this should read 1941
as the one below.
I wonder when the Authorities changed this?