Is there an earliest time one may begin Shabbat during the summer months?
We were traveling south and stopped at a Jewish community for Shabbat. The Shul there davened Mincha friday at 6:10, then added an extra prayer between Mincha and Kaaballat Shabbat to add 3 or 4 minutes. The Rabbi's explanations was they needed to add the extra time so as too not daven Maariv before the "earliest allowed time". I never heard of that before and was confused since it was still daylight out while walking back after davening was over.