Keep in mind that this formula will return the current Friday even if the completion date is that same Friday, or even Saturday for that matter.
If these edge cases are of no concern then you can use the formula as is.
Otherwise you want to add 1 (for Saturday) or 2 (for Friday) days to the finish date before calculating the week start so that it gets pushed into the next week
FirstDayOfWeek([Actual Finish Date]+Days( "1 or 2" ))+Days(5)
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Simon H
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