I'd reckon because a private company is getting paid to manufacture and sell the vaccines, at "Cost of Goods" initially, then at a profit after an agreed period

I'd reckon because a private company is getting paid to manufacture and sell the vaccines, at "Cost of Goods" initially, then at a profit after an agreed period, in exchange for funding and, eventually more profits. These are pre-orders for a vaccine, and the contract has a section on how it will be funded. AstraZeneca is under no obligation to not do business with anyone else (provided they can meet their contractual obligations). If the both the UK and the EU wanted a million doses each and AZ has the capacity to manufacture 5 million, then nothing stops them from entering into other agreements with countries in Africa, South America, or Oceania. They probably overestimated their capacity and are now pushing back on deadlines. I don't have much to criticise AZ for on that since we've all been there, but you can't tell a paying customer that you have other customers that paid you first, when you signed a contract agreeing to meeting certain deadlines. It simply does not matter. Did AstraZeneca lie in their negotiations regarding their capacity? Let's also remember that this was likely brought up when discussing the funding for manufacturing sites in Europe and the UK.