"On average how long does it usually take for a fresh comm pilot to work his way up the ranks and onto a twin in Maun?"
A very longtime seeing as you can now count the number of twins in Maun on about three fingers
. Caravan's have replaced just about all of the Islander's. Most of the companies have no twins anymore. Only a handful of pilot's that go to Maun get any twin time there, most move on to other places for the lure of twin time.