<div dir="ltr"><div>As I understand it, Europe/London switched to a "permanent" one-hour offset from GMT on 1968-10-27; time was referred to as "British Standard Time" which, for better or worse, has the same BST abbreviation as "British Summer Time." Europe/London reverted to the "old" rules on 1971-10-31. My sense is that Paul is correct and that isdst should be 0 for the 1968-1971 period.<br><br></div> @dashdashado<br></div><div class="gmail_extra"><br><div class="gmail_quote">On Mon, Sep 15, 2014 at 1:20 AM, Paul Eggert <span dir="ltr"><<a href="mailto:eggert@cs.ucla.edu" target="_blank">eggert@cs.ucla.edu</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span class=""><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Looks like isdst should be 1 on<br>
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Europe/London Sat Oct 26 23:00:00 1968<br>
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The convention is that if clocks are the same all year round and if this appears to be intended to be permanent, the isdst flag is zero even if the enabling legislation uses phrases like "daylight" or "summer". An example of that is the Turks & Caicos change in November.<br>
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My vague impression is that that three-year period you're talking about was intended to be permanent. I haven't researched this, though.<br>
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