Does Ellen White affirm the correctness of the October 22, 1844, date? QSEW 17.3
Yes. She states: QSEW 17.4
“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 twenty-second 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. QSEW 17.5
“The computation of the prophetic periods on which that message was based, placing the close of the 2300 days in the autumn of 1844, stands without impeachment.”—The Great Controversy, 400, 457. QSEW 17.6