The Politico article featured upthread mentions the following regarding the supply chain:
The order form said that four plants would provide drug substance, including the Oxford Biomedica and Cobra Biologics based in the U.K., Halix in the Netherlands, and Novasep (now Thermo Fisher Scientific) in Belgium.
[ . . . ]
Despite the fact that all three British sites, as well as the Dutch and German subcontractors, are clearly included in the supply chain,
It's not clear from this second extract if they are only talking about the aforementioned component suppliers, or are referring to the two manufacturing plants and the fill / finish site - although the latter sounds feasible I would like to see the actual wording covering both.