https://learn.microsoft.com/en-us/azure/data-factory/data-flow-date-time-functions
add Adds a pair of strings or numbers. Adds a date to a number of days. Adds a duration to a timestamp. Appends one array of similar type to another. Same as the + operator.
addDays Add days to a date or timestamp. Same as the + operator for date.
addMonths Add months to a date or timestamp. You can optionally pass a timezone.