What I would like is a calculation that would take return the value of the Thursday before my [TargetDate] value.  If it is on a Thursday, it too has to be the Thursday before.  This is to make sure that the form is submitted before the target date.

I found this, but looks like I'd have to do a WEEKDAY statement for every day of the week

http://sharepoint.stackexchange.com/questions/79499/how-to-default-a-date-field-to-a-particular-day-of-the-week

Can't seem to wrap my head around this one!  Any help would be greatly appreciated!