If the Commission earnestly believe the contract isn't being followed, why are they not pursuing legal enforcement? Why are they playing media games, hostile briefings, demanding AZ publish the contract? Why are they making political threats around export bans?

When AZ publish the contract, people will see it is littered with 'best efforts' breaks and opt-outs like the Curevac one that is in the public domain.

CureVac's APA dates from 17 November. AstraZeneca's was the EU's very first one, back in August last year. There's no guarantee the clauses will be identical or even similar, but the CureVac one (which, you'd hope, would be the more evolved), is spotted with get-outs over potential delays in delivery. If AstraZeneca's APA is anything like CureVac's, it would go some way to explain how the company has been seemingly able to fall short of its commitments to the EU. And why the commission has had to resort to means outside the agreement to try and enforce it, such as potential export measures.

This won't matter, because the EU will just quibble (in the media of course, not the courts), with the definition of 'Best Efforts', which they are already doing. They'll do this to unjustifiably imply that the UK needs to open up it's vaccine capacity to them, which it won't do. Then they have the Casus Belli they need to enforce the export ban that they want. It's a temper tantrum of epic proportions. If they had legal recourse, they'd be pursuing this legally, not through threats and pure power politics as they are doing.