[fixes] added implementation time to the due date calculation

locations/din_bad.qsrc

@@ -687,9 +687,10 @@ $d_cycreport_update = {
 
 $d_cycreport_upduedate = {
 	!! Ovulation is ~7d after menstruation
+	!! Implantation takes several days: Average is 5
 	!! Human gastation period: 280 days
 	!! ovu_calc: Days since last ovulation
-	ovu_calc = daystart - lastmens + 7
+	ovu_calc = daystart - lastmens + 7 + 5
 	temp = 280 - ovu_calc
 	pregdueday = day
 	pregduemonth = month