From the Guardian coverage of today's press conference (contradicting its own headline):
Whitty played down the suggestions that millions of coronavirus antibody tests might be available next week. A Public Health England official suggested this at a committee hearing this morning. But Whitty said:
I do not think, and I want to be clear, that this is something that we’ll suddenly be ordering on the internet next week. We need to go through the evaluation, then the first critical uses, then spread it out from that point of view. We need to do that in a systematic way.