Oh boy, where to begin
It's a complex story with a lot of conflicting reports coming out. From my understanding: Astrazeneca annoucned deliveries to the EU would be reduced with 60% because of production problems. The EU tried to 'force' AstraZeneca to its contractual agreement to deliver the doses but it appeared AstraZeneca never had a duty to deliver a certain amount, just a 'best efforts try'.
There are two separate supply chains at AstraZeneca: UK and the rest of Europe. The UK chain doesn't face the same production issues and reduction. The contract between the UK and AstraZeneca was signed 3 months prior to the EU contract. The EU claims they are being disadvantaged compared to the UK and relations with AZ have gone bad.
They fvcked it up by not naming the actual number of doses in the contractual agreement and signing the agreement too late.
On top of it: the German health authorities decided not to vaccinate 65+ year olds with this vaccine. Hungary decided to buy Putin's vaccine so by time the unified vaccination strategy is becoming different per country and crumbling. It also appears that Pfizer and Moderna are facing supply issues in the EU supply chains. So in the end we're fvcked as a collective and it appears the UK and US are actually better in containing this crisis.