Make sure you use a good outfitter for the drop. It is rare, but I hunted the south slope of the Books range one year and missed the migration. We were hiking in from the haul road, which had a five mile corridor for bow hunting only. We set up camp near the road and hiked five miles each morning to start our hunt. After a few days, we ran into a AK Fish and Game employee who told us the migration was two weeks late, so we might as well go home and return later. But a good outfitter will know where the herds are and can drop you near the migration routes. Good luck, dress for all weather and have fun.
I'm going to the north slope in Aug on an unguided hunt with a HS buddy. We went through outdoors international for their drop off service and we are renting camp gear from them as well. It's a couple hundred extra per person but everything for camp is provided, including food. We bring only sleeping bags and hunting gear. It's a great option since we don't have all the needed camp gear.