Since the time between the original and the bound volumes is short, there must have been second thoughts about the statement early, perhaps while it was being used in the WT Study.
But the Society will never stop the preaching work, even though there is clear evidence in the NT that not all Christians were "evangelizers." If they stopped it, they would have nothing to keep us in line with. Nothing to give us the superior attitude of preaching something that has never been preached before.
Talk about reinventing the wheel. The Gospel did not wait for Jehovah's Witnesses to come along before it was preached! Were it not for Catholic Bible scholars and the King James Version of 1611, we would not even have the name, "Jehovah."
Obviously, the reason Armageddon hasn't come yet is because we haven't preached enough! "Preach! Preach!" Otherwise, says the Evil Slave, "my master is delaying"! Keep on beating the flock to do more, more, MORE! (Matthew 24:48, 49) Which Slave does the Society prove itself to be???
Jehovah shows that He doesn't care about the ruminations of the Watchtower Society, simply by refusing to bless their time tables and "prophetic" mutterings.