Thank you for your help!
So... what is the real meaning of the quote on the Proclaimer's book? The quote is this one:
"This was influenced by the belief that the seventh millennium of human history had begun in 1873 and that a period of divine disfavor (of equal length to a former period considered to be one of favor) upon natural Israel would end in 1878. The chronology was flawed because of relying on an inaccurate rendering of Acts 13:20 in the King James Version, belief that there was a transcription error at 1 Kings 6:1, and failure to take into account Biblical synchronisms in the dating of reigns of the kings of Judah and of Israel. A clearer understanding of Biblical chronology was published in 1943, in the book “The Truth Shall Make You Free,” and it was then refined the following year in the book “The Kingdom Is at Hand,” as well as in later publications."
There's another quote:
"Later on, during the years from 1935 through 1944, a review of the overall framework of Bible chronology revealed that a poor translation of Acts 13:19, 20 in the King James Version, along with certain other factors, had thrown off the chronology by over a century. This later led to the idea—sometimes stated as a possibility, sometimes more firmly—that since the seventh millennium of human history would begin in 1975, events associated with the beginning of Christ’s Millennial Reign might start to take place then."
Also:
"See “The Truth Shall Make You Free,” chapter XI; “The Kingdom Is at Hand,” pages 171-5; also The Golden Age, March 27, 1935, pages 391, 412. In the light of these corrected tables of Bible chronology, it could be seen that previous use of the dates 1873 and 1878, as well as related dates derived from these on the basis of parallels with first-century events, were based on misunderstandings."
So I would guess that the changes all ocurred from 1935 until 1944? They slowly weaned off the Russell chronology?