Seventh-day Adventists claim that in 1844, a very small Jewish sect called the “Karaites,” used a different calendar and thus celebrated the Day of Atonement (10th of Tishri) on October 22, one month later than the Rabbinical/Orthodox Jews who did so on September 23.
– Truth or Fables
The tenth day of the seventh month, the great Day of Atonement, the time of the cleansing of the sanctuary, which in the year 1844 fell upon the 22d of October, was regarded as the time of the Lord’s coming. This was in harmony with the proofs already presented that the 2300 days would terminate in the autumn … the close of the 2300 days in the autumn of 1844, stand without impeachment.
– Ellen White, The Great Controversy, pp 400, 457
One of the major reasons why Adventists cannot discard this date is that a prophet of their church has stated that this was the date. Either they have to acknowledge her error, or they have to stick to their non-date. To do so, they pretended that the Karaite Jews used this date.
Karaite statements from Truth or Fables:
Yom Kippur must have been celebrated by the Karaites in late September 1844 in accordance with the 19 year Rabbinic cycle and not in late October 1844.
In the year 1844 it is on Monday 23rd September for the Karaite and Rabinnical.
Documentary evidence from the time confirms this.