One key question would be if moving to BT 5.1 improves the reliability of the stereo pair connection. I’ve tried that on first gen A1s, but dropouts have discouraged me from using it more often - which is a shame because they really do sound great in stereo. I have successfully used a wired solution with a L/R splitter and separate 3.5mm cable runs to each speaker, but that really defeats the benefit of being able to wirelessly stereo pair.
Jeff