From April 21st the new regulations are in force. If it says on the sign 45 minutes it means 1 hour, and if the sign excludes Sundays that means Bank Holidays as well.
The single yellow lines in Barton Street from Orchard Court East and perhaps in other places I have not spotted are not included in the hours or Bank Holiday relaxation. I can only assume that this is an oversight but I understand from Tewkesbury Toilets that tickets were issued by TBC outside Kingdom Hall on Sunday.