Date: Fri, 3 Aug 2018 13:10:15 +0100 From: Jon Skeet <skeet@pobox.com> Message-ID: <CA+5fHtL1aMO2e_oBoj4QGEHmJvYJ1-uykXDb2r4a=kVkzw+=uw@mail.gmail.com> | For example, my code to determine transitions got stuck [...] | because multiple UTC instants end up mapping to the same local time If that is a problem for your validator, then you need to fix it, as that kind of thing can easily happen, whatever the codebase is. Simply consider what would happen if Kiribati decided to swap back to the other side of the date line (revert to its previous zone offset). There would be almost an entire day of duplicated local times (some date would repeat in local time, more or less - either that or there would be an "invented" day (Feb 29 in a non-leap year or April 31 or something similar, which would cause even bigger problems.) kre