Here’s another news story from that date... from the original story (not the May update)
Officials say the vaccine depletes antibodies created by a person’s body that has successfully recovered from COVID-19. As a result, their plasma is no longer useful to someone critically ill with the virus. Convalescent plasma therapy was authorized by the FDA to be used by people suffering from COVID-19.
From your link....
...Update - May 27: We have an update to the story below that we brought you in February. At that time, a representative of the American Red Cross said the organization’s policy was to discourage convalescent plasma donations from donors who previously had COVID-19 and were then vaccinated because of a then-belief about antibodies. While the Red Cross discontinued dedicated COVID-19 convalescent plasma donations on March 26 due to declining hospital demand and sufficient industry supply, a Red Cross representative now tells us that based on FDA guidance, individuals who had COVID-19 and were vaccinated could donate convalescent plasma....
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They keep calling it a ‘lack of demand’ .... interesting, yes?
Looks like I was still composing when you posted, since we both quoted the same article. LOL