Hi,
ProgramChange does'nt change MIDI channel. ProgramChange i to select sounds in soundsources that somehow allow it.
In your controller manual you can read how to work with and change MIDI channels. You can't use the pads to change MIDI channel.
This is from the manual:
"2.1.1. Changing the MIDI Channel
The MIDI channel of the KeyLab MkII can be changed by holding the MIDI Ch button and
pressing one of the first 16 keys on the keyboard. After this all controls that have been set to
follow the User MIDI Channel will change to that channel.
For example, to change KeyLab MkII’s MIDI output to channel 8, hold the MIDI CH button
and hit the lowest G on the keyboard."
I suggest you read the manual.
I don't have an Arturia controller.
I have no idea about East/ West instruments.