Autoboost formula: Determining day of week

Trying to have autoboost look at a date when an item is created and tell me in a status column whether it’s a weekend or a weekday (in order to later use another autoboost to add days to weekend items).

This formula doesn’t seem to work:

IF(WEEKDAY({:coral: Assignment’s When}) IS 1-5, “Weekday”, IS “6”, “Saturday”, IS “7”,“Sunday”," ")

Likely because WEEKDAY isn’t supported by Autoboost. Any idea of how I can manage this?

I can use a Monday formula column to get the day of the week but Autoboost can’t see that column at all (likely because it’s a formula column?)

Thanks in advance!