Should be good dates for some rut action early on. Sounds like you're familiar with and close by to do lots of pre-season of scouting in.
Herd has taken a bit of a hit in recent years IMO but there still are some good ones around. High hunting could be fun early, but I suspect you'll have the best chances of encounters and success down low near the river.
Go make friends with the farmers and locals starting now. There is a wide range of opinions about both elk and hunters, so don't be surprised if you get the door slammed or asked to pay a fee. Boat access options shouldn't be out of the question either; happy to put you in contact with some guys who run the river regularly.
Attached is a recent one from that unit. PM and we can talk more.