"We’re told until the EF 200-400 f/4L IS 1.4x production reaches demand, Canon will not be producing the replacement to the long-in-the-tooth EF 100-400. "
LOL Based on my experience with Nikon's 200-400VR and the new 80-400VRII, if/when Canon update and release the 100-400L, trust me, that will take care of any and all excess demand with the 200-400IS II.