Here you go:
https://ravncrews.com/?p=newPilots
According to the Airline Pilot Central airline page for Ravn, it says the most junior captain was in June 2011... So 6 year upgrade which sounds about right. They are advertising 41k FO pay. Management for Hageland said we get 15k cash bonus paid out every 4 months in 5k increments. They mentioned Corvus FO's are eligible for it too. All you need to get it is ATP minimums.
Ravn/Corvus is great if you want to live in Anchorage and be home every night. Its all day trips out to the villages and then back to Anchorage at the end. Hageland is the highest paying 135 company in the U.S as far as I'm aware of. Corvus pays really well, I believe 41k FO pay. Plus now the 15k cash bonus each year. (You may have to ask their chief pilot about it and see how long it lasts for)
I've talked with a few Corvus guys that have mentioned other captains getting hired straight to Alaska Airlines from there. But the 5 to 6 year upgrade time isn't the best in the world. Even if they do pay a lot, quality of life trumps pay especially dealing with Anchorage / Alaska.