Is about this creature https://www.inaturalist.org/observations/25606030
discussed here:
https://forum.waarneming.nl/index.php/topic,469101.0.html
https://www.insecte.org/forum/viewtopic.php?f=45&t=113694
https://www.insecte.org/forum/viewtopic.php?f=45&t=195217
and documented here:
http://www.bmig.org.uk/sites/www.bmig.org.uk/files/bulletin/BullBMIG27(2014)p03-26_Gregory-Eden.pdf
Seen before in the Netherlands
https://waarneming.nl/waarneming/view/4090280
https://forum.waarneming.nl/index.php/topic,45738.0.html
If you visit a shop in the Netherlands where they sell Lavendula plants (and many supermarkets do in spring) check them for Armadillidium with a rounded (=afgerond) telson and make some pics of the creature…