Check in is 4pm. NOT before. Check out is 11am.
I believe check in is 4pm and check out is 11 am, but if you get there early go to the front office and let them know you have arrived and they will give you access to the pools if you wish and you can access the pools until 6pm on the day of check out as well
Get an answer from The Springs Resort & Spa staff and past guests.