Your observation about repotting in the spring is similar to what I have experienced here in the fall... we have different rainfall patterns, which helps explain why we might treat them differently.
I prefer potting the Pachypodiums in spring or summer and avoid repotting in the fall, in large part because winter is when we get most of our rain, and I don't see the point of making that any riskier than necessary. Most of my Pachypodiums live out in the rain or get moved under cover (still outside) when the rain comes at a particularly bad time. None of them come indoors for the winter because we don't get below 45ยฐF and it always warms up into the 60s or higher during the day.
On the flip side, we get zero rain in summer (yes, not ideal for most Pachypodiums
) so the spring/summer repot is way safer for me that way. I get to control all the water the plant will receive for months, for better or worse.
It would be great to see some more Pachypodium flowers, Ursula.
Here the saundersiis are all decked out in white, and I'm hoping a moth stops by.