Hello Ermias,
I think the best way to achieve this would be to use the NextDayofWeek([Assignment Date], 3) to find the next Wednesday and then add 21 days. I think this may work.
if(DayofWeek([Assignment Date] !=3,
NextDayofWeek([Assignment Date], 3) + Days(21),
[Assignment Date] + Days(21))
The only caveat is you did not really explain what happens if the assignment date is a Thursday. Is it then the third Wednesday after the next Wednesday, or is that next Wednesday part of it, then that would make the formula more complicated, but still doable.
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Brandon Drake
JHI Group
Monroeville OH
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