Thanks for the heads-up. Proposed patch attached, which changes the predicted transition from the last Saturday in March to the fourth Saturday in March. The changed prediction affects not only 2018, but also 2019, 2024, 2025, 2029-2031, etc. The predicted transitions are from 01:00 to 02:00, as before. Please let us know if you can think of a better guess. Unfortunately, this is not much notice for a change that will occur in eight days. Expect a new tzdb release soon. I think most users won't be updated in time, though. Is there some way we can inform the Palestinian authorities of the issues involved? Please see <https://codeofmatt.com/2016/04/23/on-the-timing-of-time-zone-changes/>.