I used to fairly confidently be able to buy shoes from shops online but recently size 8s now sometimes mean an EU 41 or EU 42 - and some shops have either sizes listed as size 8?
There are some shops I would never buy shoes from as they would never fit me (H&M, Zara) but now M&S and Adiddas and more seem to also be really confused about what a size 8 shoe is.