Yahrtzeit of the Baal Shem Hakadosh (belated)

The Rebbe, shlit"a, at the kever of the Baal Shem Hakadosh

There has always been some controversy as to when exactly the yahrtzeit of the Baal Shem Hakadosh is. It is well-known that he was niftar on Shavuos but whether it happened on the first day or the second day has always been a mystery.

I recall hearing in the name of the Rebbe's brother, HaRav Shloime of Denver, ztz"l, that the Baal Shem Tov was indeed niftar on the first day of Shavuos, but since it was Yom Tov they could not bury him until they found goyim to help with the malachos of the burial. Turns out that the Baal Shem Tov was buried on the second day, hence the beginning of the confusion. Apparently as the years went on, some remembered when he was actually niftar, while some remembered (correctly) when he was buried and confused it with the day he passed away.

In corroboration with this mesorah, I came across a mekor that proves without any shadow of a doubt that the Baal Shem Tov was niftar on the first day of Shavuos. The famous talmid of the Baal Shem Tov, the Toldos Yaakov Yosef, had a son named Rav Avrohom Shimon of Rashkov who was also a student of the Baal Shem Tov. Within the last few years, his handwritten siddur was discovered. By Birkas Kohanim he wrote a certain kavanah that he heard from his rebbe, the Baal Shem Tov. When attributing it to the Baal Shem Tov, he adds "who in our many sins passed away on the first day of this past Shavuos." Below is the page where this line is written (in the box).