Indications are that he'll be ready for the RS. Gives young guys an opportunity to make a splash in the PS. As for Reddick, I'm pretty sure he's familiar with the ILB position in the 3-4 defense.
Dude has all the athletic talent one could ask for in a LB. His biggest issue seems to be between the ears. Once he can get a good understanding of where he needs to be, I have no doubt he can physically get there.