Weird SONOFF switch behaviour

I have a modest HA config, with a number of SONOFF basic switches on orig firmware, using the SONOFF LAN integration on a Pi 3. I have other components which are working fine. Nothing significant has been changed recently - I accepted updates of the Core and integration recently but I’ve rolled back to an earlier version and I still have the problem.

First, after reboot some of the SONOFF switches never become available in Lovelace. Other times they are really slow. I don’ t think it’s always been like this!

I am at my PC in my office next to my router, trying to create an automation to turn on a light and a SONOFF switch downstairs in my kitchen… I can manage both devices for the automation (turn on/off, re-add etc) from Lovelace but the automation does nothing to the SONOFF switch. It turns on the light fine. If I change the target to a SONOFF switch near my computer it works.

Initially I thought it’s a problem with my network but I can manage both devices (turn on/off, re-add etc) from Lovelace.

I’ve re-installed the integration, and deleted the sonoff.json, and tried it under different browsers and from my phone - no luck.

I’m at a loss what to try next. I’m not sure whether there is any SONOFF/integration logging I can do. I am open to suggestions please!!