Early as possible. You have to read, watch a video, have an physical exam, do the electronic questionnaire, the regular tests that they do every time, and the actual donation which takes around 45 minutes. At least 3hrs before closing. You don't want to go through all that then have to come back to finish the next day. Make sure to bring the proper documentation and lots of patience. Good luck.
For new donors, I would go in as early as you can. At least 3 hours prior to closing time so that they can get you processed.
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