There's no logic behind this. Even if you go by the reasoning that 12 PM is noon because any time after exactly 12 PM sharp is post-meridian if the meridian is

There's no logic behind this. Even if you go by the reasoning that 12 PM is noon because any time after exactly 12 PM sharp is post-meridian if the meridian is exactly at 12, it shouldn't be 12 but 0. Having an intentional off-by-one error in your date format is simply bad design and counterintuitive. The 12 hour date format with AM/PM is asking for trouble and it's at least partially their fault that you got this wrong, especially if they schedule appointments at unusual times and expect you to find noon and midnight equally reasonable. They could have avoided this easily but their lack of accomodation shows an intentional disregard. If it's any consolation, Pearson is infamous for horrible exam designs, so at least they're not uniquely shitty towards non-Americans.