See: https://yamahasynth.com/forum/superknob-control-by-fc7#reply-8433

What you are seeing is behavior that is part of the Yamaha synth DNA for generations. When you switch performances, many of the controllers will not match the programmed values. Say you change from some organ patch you've been using the FC7 to set the volume (swell) on the organ and ended the song with the pedal at full volume (toe down). Then you switch to CFX + FM EP which uses the same FC7 to control the amount of EP (DX7 like electronic piano) vs. CFX (acoustic piano). The default for CFX + FM EP is that the sound starts with acoustic piano. When the FC7 is in the toe-down position - this would normally tell the Performance you want the electronic DX7ish piano to be fully sounding (and no acoustic piano). However, when you change from one performance to another - Montage assumes you favor the programming of the Performance which sets the default to the performance programming. In this mode, not until you "pass through" the programmed value (of pedal at full heel position) do you "snag", "catch", or "hook" the value for direct control.

You have a few choices.

You can do what I did before with the sliders - and move the controller back and forth after a Performance change so that your controller (in this case the FC7 foot pedal) can "hook" the value for direct control.

You can setup the the controller reset state to "HOLD" which will not reset the controllers and should keep the current values. This applies to all controllers - not just the foot controller(s).

https://yamahasynth.com/forum/fc7-and-performances-volumes#reply-2489 (yes, for another keyboard - but description remains the same)
... and for Montage:
https://www.yamahasynth.com/forum/foot-controller-doesn-t-work-with-usb-volume#reply-21796

Or you can reprogram your performances so the programmed value starts in the area of where your previous performance ends so that it is easier to "catch" / "hook" without having to travel the foot controller fully back and forth.

Hey Jason,
Thank you so much for your thorough answer! Now that I know that this is a common behavior I'm relieved. I'm just starting to learn about this instrument. It seems like your first suggestion works best when switching performances in between songs (which will be the case for me most of the time I assume). And the 2nd suggestion you made might come in handy if a performance switch has to happen in the middle of a song. I'll check out those threads. Thanks again and enjoy the rest of your weekend.
Marcus