I'll be honest, I'm not 100 percent sure, it should just allow the spring to avoid binding, but I feel that the binding may assist in driving the roller into the notch before it upshifts past that point.
I only have that issue when I try to reverse uphill quickly, like looking over a cornice & I realize that I'm off from where I think I was planning on dropping. (if it is a slight downhill cornice) If I get overzealous it tends to pop out.
Make a point of being more deliberate about how you drop into reverse & you'll likely be able to avoid this in that future. On my little sled just changing habits has done the trick.