Not sure if there is any hardware limitation, but it would be great if FX8 supported the new block channel feature.
Herer is the description of it from AxeFx III page.
"Our new “Channel” concept is a revolution in functionality. Each effect block has up to four channels with each channel containing a unique set of parameter values. Channel switching is instantaneous and seamless and can be done manually (via a foot controller, for example) or automatically when changing scenes. Channels can also be switch via MIDI for applications requiring automation."
Herer is the description of it from AxeFx III page.
"Our new “Channel” concept is a revolution in functionality. Each effect block has up to four channels with each channel containing a unique set of parameter values. Channel switching is instantaneous and seamless and can be done manually (via a foot controller, for example) or automatically when changing scenes. Channels can also be switch via MIDI for applications requiring automation."