Morning stiffness post op

Hi all, I’m 29F 8 weeks post L5/S1 fusion. I’m wondering when other people noticed a significant improvement in stiffness in the back when waking in the morning? At the moment I’m stiff as a board when I get out of bed and shuffle around for a good hour before feeling some kind of normal. I’m using heat packs which helps loosen things up but would love to know at what point others started waking up not feeling so sh!t.