When stickler for punctuality Edward (played by Ted Ray) arrives at his office building, a huge outdoor clock clearly gives the time as 9.30. He then walks into the office, where an equally huge clock shows the time as 9am exactly.
When Ted Ray is talking to his wife in the tea shop, he places his hat on a stand next to their table. When they leave the hat is no longer on the stand but in his hand.
Not that it matters, but Jo couldn't publish a book without her parents knowing because she is under 21 and so can't sign a contract. The age of majority (when a child legally becomes an adult) was 21 at that time, and was only lowered to 18 in 1970.