The blood supply is not being replenished as fast as it is being used right now. If they get an unscheduled donor, they're not going to turn them away. Yes, waiting 20 minutes to donate may be inconvenient. I'm sure that if they are routinely not able to meet scheduled appointments, they will eventually do away with them. It sounds like you either had bad luck, or you just happen to be scheduling yourself for times where they may be apt to get more walk-ins. My past two donations, I haven't had to wait even five minutes. Even so, I schedule it on my day off, a month in advance, and don't schedule anything immediately after, in case I were to run into trouble, medically. A person who needs blood right now because they lost theirs unexpectedly, cannot wait 20 minutes. Be grateful to your deity that you are not that person today. We give, because they're going to need.
I walked in for a 1:00 appointment on Tuesday. I was taken in at 1:00. Better than at one of the Mobile Centers.
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