Wait.. Wait... I can do this.
I'm going to assume probably 30 as planning hours.
So 272/18= 15ish/2 = 7.5 hours per day.
Holy shit!!! Attila!
Let's assume 60 hours as planning hours
242/18= 13.4/2= 6.7 hours per day.
Not to judge or anything, but your work party would've sucked... Sweet...