This is really neat, but you need to rethink the date/time/duration arithmetics. You’re equating 12 months with 365.25 days, which gives rise to results like “1 month - 31 days” giving “-0.0184804928 months”. At the same time, “30th January + 1 month” gives “28 Feb 2022 at 12:00:00” (why “2022”, and why “at 12:00:00”? — this is only a date calculation without reference to a year or to a time of day), while “30th January + 30 days” gives “1 Mar 2022 at 12:00:00”, although “1 month in days” gives “30.4375 days”.<p>In reality, months/years are simply not convertible to days/weeks arithmetically, and you can’t sensibly add months to certain dates, and sometimes also not years (for February 29th). The former should give “Incompatible units”, and the latter should result in something like “Undefined” for incompatible dates.