You don't get early entry but they do open the gates to all around 30'ish mins before park opening and you can check in/get your wristbands and cups/etc and many (maybe all?) of the shacks are in areas that are accessible at that point while paths further into the park are still roped off until park opening time. Time it well and you can get there/get unpacked/sunscreen on/etc and be primed to hit the rides right at rope drop. I'm not sure if that applies to all of the shack locations though, the last three we have have had been in the 21-27 area in the image below and that are is accessible.
I am anal with by water park arrival strategy and definitely like to get there early to be among the first in the tapstyles, among the first at High N Dry to check in for the shack, etc. Those are valuable minutes to use wisely, IMO... because we like to hit the rides hard for an hour before crowds build in.
Have fun!