Fisherman,
Actually Watchtower only uses "circa" when referring to when war broke out in heaven and Satan was ousted. They started acknowledging that "about" was better to say when it was pointed out that WW1 started in the Summer of 1914, before their interpretation of October as the end of the gentile times and when Satan was ousted from heaven to the vicinity of the earth. This was a problem so now they just say that war in heaven could have broken out before the gentile times ended, before the Summer when the war broke out. Disconnecting the 2 events helps explain the 6+ months needed for Satan to 'land' on earth and foment enough discord to start a world war.
Nevertheless, most reputable historians say 587 BCE was the actual year of Jerusalem's destruction - not 607 BCE. That would make 1934 the momentous year. But you already know that and have tried unsuccessfully on this forum to redact what you must surely know to be the truth. But you are consistent so there's that...