Hi, thanks for the feedback.

We've made changes to how our API works and Chanukah candle-lighting times will no longer suppress regular Shabbat/Havdalah times. Here's an example to illustrate how the API now behaves (with 2 events on Friday night and 2 events on Saturday night).

https://www.hebcal.com/hebcal/?v=1&cfg=json&maj=on&min=off&mod=off&nx=off&year=2019&month=12&ss=off&mf=off&c=on&geo=zip&zip=11581&m=47&s=off&b=18&leyning=off

    {
      "title": "Candle lighting: 4:16pm",
      "date": "2019-12-27T16:16:00-05:00",
      "category": "candles",
      "title_orig": "Candle lighting",
      "hebrew": "הדלקת נרות"
    },
    {
      "title": "Chanukah: 7 Candles",
      "date": "2019-12-28T17:22:00-05:00",
      "category": "holiday",
      "subcat": "major",
      "hebrew": "חנוכה: ז׳ נרות",
      "link": "https://www.hebcal.com/holidays/chanukah-2019?utm_source=js&utm_medium=api",
      "memo": "Hanukkah, the Jewish festival of rededication. Also known as the Festival of Lights"
    },
    {
      "title": "Havdalah (47 min): 5:22pm",
      "date": "2019-12-28T17:22:00-05:00",
      "category": "havdalah",
      "title_orig": "Havdalah",
      "hebrew": "הבדלה (47 דקות)"
    },
    {
      "title": "Chanukah: 8 Candles",
      "date": "2019-12-29T17:07:00-05:00",
      "category": "holiday",
      "subcat": "major",
      "hebrew": "חנוכה: ח׳ נרות",
      "link": "https://www.hebcal.com/holidays/chanukah-2019?utm_source=js&utm_medium=api",
      "memo": "Hanukkah, the Jewish festival of rededication. Also known as the Festival of Lights"
    }

The Hebrew Date Converter now supports BCE dates

https://www.hebcal.com/converter?hd=11&hm=Sivan&hy=1234&h2g=1

11th of Sivan, 1234 = Sat, 9 May 2526 B.C.E.

Hi Neil, thanks for being a long time Hebcal user and reporting this bug many years ago. Although we corresponded privately recently, I'm also answering this question here for others who may be searching for the answer.

We were finally able to reproduce this error on Outlook 365 web. We made two changes to our iCalendar feeds to fix the problem for you:

1. Our .ics feeds so they include X-MICROSOFT-CDO-ALLDAYEVENT:TRUE which according to some Microsoft documentation might fix the problem.

2. Our VTIMEZONE implementation for Asia/Jerusalem (the timezone that is used throughout Israel) has been modified so it only uses a simpler, current Daylight Saving Time rules (which clocks are advanced by one hour, beginning on the Friday before the last Sunday of March, and ending on the last Sunday of October). This is perfectly accurate for any calendars 2013 and later (when the Israeli government standardized and simplified DST rules).

Shana Tova!

Thank you for the bug report! We found the cause of the error (an incorrectly set background color) and we have fixed it. If you refresh the page it should appear correctly again.

We have added this feed to to https://www.hebcal.com/ical/