That's an interesting page. Thanks. It's useful to me, as the UK actually is part of the European Union and has been since 1973
I have to ask, though, if you're already aware of this stuff, then why are you asking here?
The thing is, Sony would probably argue that it's overridden by the fact that you agreed at least 3 times that unlocking your bootloader may invalidate your warranty during the process of retrieving the unlock key from their website. Even though statutory rights cannot be overridden in this way, that hasn't stopped warranties being denied for no good reason before. This is a moot point though, as long as you restore your TA partition before taking your phone for warranty repairs.