Adding column in Views for completed submission plus several days
I have solved my own problem. Using Views PhP module.
Add field Global:PHP,
in the output code box:

&lt;?php
$correctdate = $row-&gt;completed; 
$correctdate1 =strtotime("+7 days", $correctdate);
$cdate = date("j/n/Y - g:i a", $correctdate1);
echo ($cdate);
?&gt;