Toe and Heel expression cc messages

Is there any more information about HOW TO USE the Heel and Toe expression cc messages on the MC8?

Trying to use an midi expression pedal for the first time with an MC 8.
A blog or article about the various usage and techniques would be extremely useful……
I am getting confused about how to implement this on my Strymon pedals.

I can use my boss ev30 pedal to ‘wipe’ single (and multiple) MC8 expression CC messages.
But I just don’t know how to set the heel and toe parameters.
As I understand it, this HAPPENS regardless of the settings on the Strymon stomp box, such as EP MODE, EP ON/OFF, HEEL & TOE SETTINGS etc. Etc.

I have managed to find a way of RESTORING a preset after changes by the expression pedal.
Just do a STRYMON BANK UP then BANK DOWN.
This then restores the original preset, and send CC#102 value 127 to enable the preset again for good measure.

HELP!