I've reverted to using the Generic Zigbee Switch driver which stopped the error from popping up again. One thing I found is that when I introduced Tuya Zigbee Plugs into my mess is when this errors started popping up.
The Tuya plug is also seemingly what's responsible for my Sonoff ZBMini-L2s dropping from the mesh when the switch routes through them running as a repeater.
Thankfully I had a HA setup as well, so I moved my Tuya stuff to HA and avoided dealing with this problem now.
Seems like there is some incompatibility between the Tuya plugs and the Sonoff switches…
All my Tuya Zigbee plugs are excellent Zigbee repeaters, I have a lot of battery-powered devices which are using them as routers. But I have no Sonoff switches.
The Sonoff zbmini-l2 seems very particular about the repeater it talks to. There isn't much option though, I'm not exactly spoilt for choice when it comes to small footprint no neutral relays.
Is there a way of forcing these modules to use certain repeaters (and not others) or turning off the repeating capability of specific devices to try to identify the problematic devices and establish a more reliable operation?