I've noticed that lately the WT has been using the date 1919 more often. In an almost matter of fact way, they will state that this is the year Jesus finished refining his people and appointed the FDS. The only problem is there is little proof or even prophetic antitypes given for why this must have been the year. This is the most recent explanation and it makes very little sense:
w14 11/15 p. 29-30
So, according to this explanation the first 1260 days are literal lasting from he middle part of 1914 to 1918. Even though the same "times, time and a half a time", are in other prophecies explained as being "a day for a year" and thus spanning 1260 years. However, the next three and half days mentioned in the prophecy aren't literal and they aren't an antitype either. They are simply a "comparatively shorter period of time", that so happens to bring the timeline right up to 1919. It is clear that the date 1919 is the what they wanted all along and this explanation is clumsy way to try to make it fit.
Revelation 11:3 speaks of two witnesses who would prophesy for 1,260 days. The account then says that the wild beast would “conquer them and kill them.” But after “three and a half days,” these two witnesses would be brought back to life, much to the amazement of all onlookers.—Rev. 11:7, 11.
At the end of their preaching in sackcloth, these anointed ones were symbolically killed when they were thrown into prison for a comparatively shorter period of time, a symbolic three and a half days. In the eyes of the enemies of God’s people, their work had been killed, causing those opponents much joy.—Rev. 11:8-10.
However, true to the words of the prophecy, at the end of the three and a half days, the two witnesses were brought back to life. Not only were these anointed ones released from prison but those who remained faithful received a special appointment from God through their Lord, Jesus Christ. In 1919 they were among those who were appointed to serve as a “faithful and discreet slave” to care for the spiritual needs of God’s people during the last days.—Matt. 24:45-47; Rev. 11:11, 12.
Interestingly, Revelation 11:1, 2 links these events to a time when the spiritual temple would be measured, or evaluated. Malachi chapter 3 mentions a similar inspection of the spiritual temple, followed by a time of cleansing. (Mal. 3:1-4) How long did this inspection and cleansing work take? It extended from 1914 to the early part of 1919. This period of time includes both the 1,260 days (42 months) and the symbolic three and a half days referred to in Revelation chapter 11.