4 speed getting stuck in 2nd gear outside of car

This happens when the back bearing is the wrong width.Did you change it? The A833 has a unique rear bearing; it is thicker than the standard one with the same PN. It has a special suffix to indicate that. And the last time I bought one,it cost triple what the standard one did.
What can happen is; the m/s moves rearward on the 1-2 shift, allowing the struts to pop out. If the brass ring on first sits a little low on the cone, then it can rotate out of sync with the struts, and that locks it into second.If you continue to rotate them with downshift pressure, then eventually the brass may lock onto first gear and rotate into position for the struts to re-engage. But usually the struts pop out and it's game-over.
But if it continues to work in the car, don't lose sleep over it.
Unless you changed that back bearing.
But what's the worst that can happen; you can still drive home at 60 mph with 3.55s, at the top of second,lol.

I love your car