I know my page says to wait until the next day but I now think that you should start after donating (I gotta change that wording). So if you donate at 8am, start the protocol at 9am or 10am. If you donate at, say, 1pm, start the protocol at 3pm or 4pm. If you donate at 3pm, start the protocol at 9pm or 10pm.
I don't want guys to worry too much. If you finished donating at 9:15am or something, go ahead and start the protocol at 10am. It's important to start to raise hepcidin right away.
I just did my first 5 day... the freaking gut issue of black stool was unbearable, no wonder no one has been brave enough to go 6 days yet. But I really needed to up my ferritin so I tolerated it.