You are welcome!
As is well known, a Yamaha style file can contain up to 16 MIDI channels, but only channels 9 - 16 of a style are directly visible/editable on the keyboard and are used for the style parts. However, channels 1 - 8 can contain additional patterns (e.g. for certain chord types). If I remember correctly, several MIDI channels (assigned by the CASM) were used for MegaVoices in SFF1 styles in order to be able to play back the effect notes (above C6) correctly.
I wish you a nice day too!
Best regards,
Chris