I finally found a local-ish blood center that will take whole blood. I made an appointment on their web site and drove down there this morning.
Being a techno-Luddite, I immediately ran into a problem - there was a sign instructing me to "use this QR code to sign in!" But I don’t have a smartphone, so I had to attract someone’s attention, which seemed to annoy them.
There was a ton of paperwork, which took about half an hour. They asked several times if I was sure I wanted to donate whole blood. They’re the only place in my area that will even *take* whole blood; everyone else is set up for plasma or platelets.
Once the paperwork was done they were reasonably friendly. The actual procedure took about ten minutes; half of that was fiddling with the plumbing. There was an impressive amount of that, that they tried to keep out of my direct line of sight. The needle size was, if anything, even smaller than for an ordinary blood draw, and no discomfort at all.
They offered me a T-shirt and a coffee cup when it was done. I accepted; coincidentally, Mrs. Andy collects both. I agreed to come back in two months for another draw.
The next endocrinologist visit is at the beginning of February, so depending on what the blood work looks like, I can do draws every two or three months and still bracket the 6-month endocrinology follow-ups.