My guess is they are as air dried as they can be for boards that thin. It would help to know your location to understand the drying conditions better, but if you were in Alabama, its time to bake the biscuits.
If you want to further dry them for inside conditions, bring some of them inside your house for a short while and they will come down to your house's moisture conditions.
Air dried cedar sap can still be sticky, so watch for that. Also, don't bring a huge load into your house, but enough to build a cedar chest or two won't overwhelm your HVAC system.