They got rid of this teaching in the late 70's, saying that the First WW was not as bad as even the second, which was not part of this "tribulation" so awful it had never been seen before. In that study, they put a new idea that Daniel 12 foretold the length of WW2 - 1800 odd days. that was never mentioned again, and they went back to the rinky-dinky A$$emblies in the 20s idea.
Most young witlesses dont even know of this GT teaching- they must be talking about it to put another spin on a doctrine, or to introduce a new "troof" - noolite- that depends on debunking this teaching which was forgotten for thirty or more years.
HB