Post Process Blend Speed?

In UE3 Post process volumes used to have a blend speed value (not sure if it was actually called blend speed) that you could adjust to affect the time it takes to blend in or out when you exit the volume. UE4 PP doesn’t seem to have this feature that I can find anywhere. Am I missing something or is this actually a missing feature?

you’re after blend radius

Oh ok so the size of the radius determines how long it takes to fade? Thanks!

Any idea why my Post Process volume isn’t working when I PIE but it works just flying around in the editor? I’ve got an unbound PP in the scene too so I set the volume based one to an order of 3 and the unbound to 1 but it still won’t activate in game.