[Jon]

It does seem that people are over thinking this. It’s the EBU rules that mean the arena has to be renamed for the purposes of the contest not a BBC rule. We already know Eurovision are referring to it as the ‘Liverpool Arena’. As host broadcaster the BBC are entitled to use their own branding to some extent so it makes sense for them to use their own logo to cover up the regular one.

I’m sure the BBC would have no problem referring to it as the M&S Arena as they would refer to the Emirates stadium if they were showing an Arsenal home match for example. Pretty sure for the arena based SPOTYs they’ve used the sponsor name too. But the EBUs rules prevent that for the purposes of the contest.

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They don't seem to mind referencing the sponsor of any sports events either, which I find odd. I know they can't escape having, say, the Cazoo logo dotted around the Crucible during the snooker, but their own presenters usually refer to it as "the Cazoo world snooker championship".

Because World Snooker wouldn’t be very happy if the rights holder didn’t use the official name of the competition. Even things they don’t have any rights for they’d use the correct competition name for, namely because it would be technically incorrect not to. 

Now if the BBC was receiving funding from the sponsors for this it wouldn’t be allowed. It’s like the difference between prop placement and product placement.