You have to wonder, then, why Michelin's own web-site directs you to Protyre when going to look at their tyres and not their own company ATS!! Below is what happens when you click 'Buy Online' on Michelin's own web-site.cj10jeeper said:Correct - from the Michelin website:
ATS Euromaster is a distribution network owned by the Michelin group and was created in 1965. With over 50 years of experience, the network has become one of the leaders in the market of tyre and vehicle repair services in the UK.

EDIT: It's a local ATS garage that are going to be fitting the Conti tyres next week for me, as they also apparently can't get the un-marked 4S tyre.