God’s Kingdom of a Thousand Years Has Approached (1973), pages 209-210:
In the year 1943 the Watch Tower Bible and Tract Society published the book “The Truth Shall Make You Free.” In its chapter 11, entitled “The Count of Time,” it did away with the insertion of 100 years into the period of the Judges and went according to the oldest and most authentic reading of Acts 13:20, and accepted the spelled-out numbers of the Hebrew Scriptures. This moved forward the end of six thousand years of man’s existence into the decade of the 1970’s. Naturally this did away with the year 1874 C.E. as the date of return of the Lord Jesus Christ and the beginning of his invisible presence or parousia. The millennium that was to be marked by the detaining of Satan the Devil enchained in the abyss and by the reign of the 144,000 joint heirs with Christ in heavenly glory was therefore yet in the future. What, then, about the parousia (presence) of Christ? Page 324 of the above book positively says: “The King’s presence or parousia began in 1914.” Also, in the Watchtower issue of July 15, 1949 (page 215, paragraph 22), the statement is made: “ . . . Messiah, the Son of man, came into Kingdom power A.D. 1914 and . . . this constitutes his second coming and the beginning of his second parousía or presence.”
The Watchtower, 15 August 1974 page 507:
In 1943 the Watch Tower Society’s book “The Truth Shall Make You Free” did away with the nonexistent extra 100 years in the period of the Judges and placed the end of 6,000 years of man’s existence in the 1970’s. It also fixed the beginning of Christ’s presence, not in 1874, but in 1914 C.E.
These claims, both in the lead-up to 1975, associated the change from 1874 to 1914 for Jesus' 'presence' with a mistaken view that the 6th millennium ended in 1874, replacing it with an equally wrong 'correction' that instead focussed on 1975 (essentially a red herring intended to add weight to their 1975 nonsense). This lie completely conceals the reason, the timing, and the individual responsible for shifting Jesus' parousia from 1874 to 1914 (which has already been demonstrated to have been made by Rutherford in the early 1930s). There is actually no 'natural' (i.e, obvious) reason that changing some other interpretation about 1874 necessarily meant Jesus 'presence' also had to be changed to 1914 (especially since their beliefs about 1874 and 1914 are nonsense anyway, but even if they weren't).
Though the cited 1943 book did update their nutty chronology, it didn't actually make any special point about 'removing 100 years' from their previous chronology nor did it specifically mention the 1970s (though it does say the total time for all the creative 'days' was exactly 42,000 years 🤣). Worse still, the 1943 book placed the 'creation of Adam' in 4028 BCE, so by 1974, the 1943 claim about what was to happen after 6,000 years had already failed. Little wonder they were so selective about quoting from that book.