Don't know if this has to do with my processing sequence:
NOTE: I'm not a typical Arranger Station player....
(If this is the reason I have this situation, then I apologize and there is no need to reply.)
I'll find a Left Preset that I like.... and give it a name defined in my User area.
Then I usually find a Right1 preset that I like and do the same...
But when I go to choose a Style.... I follow the same procedure, saving it to a User area.
When I go back to the main screen what shows up in the Left Voice box is a Preset again.
Usually, but not always, if I click on the Left voice box and click on the User tab.... the User voice that I chose is displayed again.
But not always.... Sometimes, I have to search through the User choices to again find it.
I don't save my settings to a Registration until I'm satisfied with all of my voice and style choices.
Don't know whether or not this has anything to do with it.