This is an interesting question because it’s the difference between clocks and calendars. If you add 7 calendar days it’s 1pm. If you add 168 hours then it’s 2p

This is an interesting question because it’s the difference between clocks and calendars. If you add 7 calendar days it’s 1pm. If you add 168 hours then it’s 2pm. Generally calendar systems will try to encode reasonable semantics for this on what a human would expect it to do. In those case it’s add 7 days. Calendars and clocks are not equivalent.