I have the following formula: =WORKDAY(A56,5,Due!$H$1376:$H$1390)

If column A has a value, then the column with the formula returns a date.
However, if column A does not yet have a value (but will in the future) then
the column with the formula returns with 01/06/00. How can I get the column
with the formula to remain blank if there is not yet a value in column A?

Thanks!!