Libyan time zone has incorrect initial transition - by Jon Skeet

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  Fixed<br /><br />
		This item has been fixed in the current or upcoming version of this product.<br /><br />
		A more detailed explanation for the resolution of this particular item may have been provided in the comments section.

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ID 787282 Comments
Status Closed Workarounds
Type Bug Repros 2
Opened 5/20/2013 6:34:10 PM
Access Restriction Public


A recent Windows Update appears to have "broken" the Libyan time zone - not in terms of the data itself, but in terms of the handling of it.

Standard time for the zone is UTC+1, and *normally* transitions in the adjustment rules are specified in local time - but that appears not to be the case here. Despite the fact that the adjustment rule for 2012 (the first adjustment rule which is present) says that there's a transition into daylight saving time at 2012-01-01T00:00:00, this appears to be treated as a UTC time. I would have expected the transition at 2011-12-31T23:00:00Z, which is the UTC time for the *local* time of 2012-01-01T00:00:00.
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Posted by Jon Skeet on 10/1/2014 at 9:58 AM
Having looked at the reference source, it's now clear what the bug is. I've updated my blog post about this issue - which affects other time zones too - with details:
Posted by Microsoft on 5/21/2013 at 6:36 PM
Thank you for reporting this issue. It is valid issue as 2012/1/1 (Libya zone time) should start the daylight time. The problem happen in the calculation when the zone rule starts at beginning of the year at 1/1 12:00 AM. By the way we don’t treat the rules dates as UTC. We’ll look at fixing the issue in the future releases.

thanks again for reporting the issue
Posted by Macy [MSFT] on 5/21/2013 at 1:07 AM
Thanks for your feedback.

We are rerouting this issue to the appropriate group within the Visual Studio Product Team for triage and resolution. These specialized experts will follow-up with your issue.
Posted by Macy [MSFT] on 5/20/2013 at 6:51 PM
Thank you for your feedback, we are currently reviewing the issue you have submitted. If this issue is urgent, please contact support directly(