Extroot Lost on Sysupgrade


I have a working system with extroot - liking the extra storage space available, it's letting me run a host of things on OpenWrt. But ... on sysupgrade, it seems that my extroot settings are lost, so my extroot partition / overlay is no longer present (having to set it all up again!). The issue isn't quite like [Solved]SD card extroot stop auto mount after firmware upgrade ... rather, it seems like the jffs2 partition is wiped. It this expected? Ways to fix this?