I need to ‘fess up and admit to being a lurker – where? On the NGW List. And why am I admitting to it now (this feel somewhat like admitting that those magazines were, in fact, mine and not from the Vicars’ son)? Because there was a post today about Timezones, again.
Yes, parts of Indiana are now going to observe DST, where they did not before and yes, that breaks stuff. What do I advise you to do? Nothing. Let me explain the conundrum. Imagine that last year someone sent out an appointment for 10am April 5 2006 in Indiana. At that time their workstation did not know about the whole DST thing going on. To store the appointment in GW the client takes the appointment time, subtracts the GMT offset (-8?) and subtracts the DST Bias (0). The time stored in GW would be 5pm. Sometime later you update your workstation TZ with the DST information. Now what happens to the appointment is we take the stored time, which is called UTC (5pm), we add the GMT offset (-8) and add the DST Bias (1) – the appointment has moved to 11am.
‘No problem’ you think, I’ll just get out the appointment time adjuster and change the time. Wrong. The problem now is that you have appointments in the PO that have both the correct UTC stored, and the incorrect UTC and GW has no way of knowing which one is which, and the appointment time adjuster just changes them all.
Really, all that you can do is send a notice for people to reschedule their appointments that are in the affected times – in Indiana’s case, this is unfortunately anything between April and October. In those places where it only shifts a week, then only appointments in that week are affected. You shouldn’t do this until the workstations have been updated though.
Now my head hurts and I am going to sign off. I’ll revisit it again, if anyone finds this useful?