It is trivia when eternity is staring you in the eye. The G-d of Abraham, Isaac & Jacob doesn't care when you start and/or end Shabbat. All He cares about is that His people voluntarily obey His instructions/directions -- choose blessings, choose life. This includes honoring the Shabbat by respecting/honoring His Name. The 613 rules of halacha are man-made inventions. Read Torah for yourself. Allow the G-d of Abraham, Isaac & Jacob to instruct you. Then do as instructed. Don't foist it upon another. Just, YOU do it. Set the example.
from the article: Ashkenazi and Sephardi rabbis battle over Sabbath hours in Elad