"Richard J." wrote in
m:

I am amazed that these changes have been made to an established
typeface which has so much exposure to the general public. Presumably
the new designs will only appear on new signs and publications, so for
the forseeable future the superseded designs will still be on show all
over the network. I'm also surprised that the design standards
documents on the TfL website don't make any reference to the changes.

Can anyone throw any light on why these changes were made?

Good question. I noticed a while ago (probably over a year ago now) that
the Old Johnstone-style "1" was used on bus destination blinds - I spotted
it on the 111.