Excel's serial number for a moment: days since 1899-12-30, in the local wall-clock time of offsetMinutes (as Date.getTimezoneOffset reports it). A date-only value keeps its calendar day. Returns null for a value that isn't a date.
offsetMinutes
Date.getTimezoneOffset
Excel's serial number for a moment: days since 1899-12-30, in the local wall-clock time of
offsetMinutes(asDate.getTimezoneOffsetreports it). A date-only value keeps its calendar day. Returns null for a value that isn't a date.