How to change the date/time on an iPhone for a COVID-19 Vaccine
As many of you know already, there is a way to change the date/time on your device to get a Walmart or CVS vaccine, pretty much on demand. (Although you have to wait until 11 pm for Walmart, 3 am for CVS for this to work.) A more detailed post on how this works is here.
The first step is to go into Settings – General – Date & Time – Turn off “Set Automatically” and choose the date/time.

Be sure to change not only the time, but the date as well. In the photo above, I did this on March 6, 2021 @ 10:50pm. I changed the date/time to March 7, 2021 @ 12:50AM.
After that, head on over to the Walmart/CVS scheduling page and schedule your vaccine. This links can be found below:
https://www.walmart.com/pharmacy/clinical-services/immunization/scheduled?imzType=covid
https://www.cvs.com/vaccine/intake/store/cvd-store-select/first-dose-select
After you sign in, and register you will be able to select the location you prefer. Yes, you can wait until the real midnight, but appointments go fast!

P.S. Don’t forget to change your time back after you schedule!