The most common thing wrong with a small shop's website is not the design. It is that it says you close at five, and you have closed at four since March.
That happens because the hours are typed in four places: the footer, the contact page, Google Business, and whatever takes the bookings. Nobody remembers all four.
So there is one place. You change Thursday, and the footer, the structured data Google reads, the open now badge and the booking form all change with it. Bank holidays get an override, so you don't have to remember to change them back.