Hi All, and thanks for battling it out, I'm getting similar results all over the internet and no straight answers. I contacted Wago themselves, they say ...
"The 222 series is suitable for 2.5mm² twin and earth, if that is what you are repairing. If the junction box is to be inaccessible when finished, you must follow the instructions for the maintenance free applications (see attached leaflet)."
Thanks. That corresponds with my understanding, and what I've been saying. I'm sure that approach would be OK.
However, as has been said previously, if you used one of the Ashley/Hager maintenance-free junction boxes (which I think is the only alternative to Wago+Wagobox), then there would be no uncertainties or scope for arguments!
Kind Regards, John