David Braverman <david@braverman.org> wrote on Fri, 28 Feb 2014 at 13:19:10 +0000 in <bf1eb347c28b440e804f199165dca2a9@BLUPR04MB037.namprd04.prod.outlook.com>:
*Schedule* to wall-clock time; *log* to UTC.
It really doesn't matter what you do with historical events, so we don't need to discuss it here. Also, it's not like this is apps-discuss-for-calendaring-software-plus-time-nuts@. Unless something goes wrong, historical timestamps really don't change, so UTC and local time can be converted between reliably. That said, for most calendaring applications, it is better to log in the timezone assocaited with the event, because if there is a change, that's much more likely to be accurate. For systems -type applications (security log of who walked into the scheduled conference room that is centrally maintained by door sensors of Multinational Corporation0, then UTC might be better. But it really should not matter. And if we're worrying about retroactive DST adjustments, well, I think there are few enough of those that I would want to look at some real cases before offering an opinion. --jhawk@mit.edu John Hawkinson