Kinematics - Changing Physics Update Mode

So I am following this but only got to step three because after deselecting the bones the Details panel just goes blank and there is no dropdowns or anything to change the physics update mode.

Not really sure what is going on. I am familiar with UE4 but took a break and now just coming back to it. Can someone please help this is driving me crazy. Anytime Is search this online I am brought to the same link.

Thank you in advanced