What is more critical is that all witnesses should know that the first interpretation of the "1335 days" was linked to a major event, that of the second coming! That's right! 539 AD + 1335 = 1874! So the Bible Students thought the 1335 days was the date of the second coming! I guess after 1874 passed without a visible second coming, they began to focus on 1914 as the second coming, but there was not relevance for it fulfilling the "1335 days" as was 1874, which they linked to the foundation of the Catholic Church in 539 AD.
Of course,1874 was based on the "a day for a year" formula, so the 1335 days was actually 1335 years! Apparently they dropped that as well and applied literal days in connection to 1914. This is from the Watchtower regarding the fulfillment of the 1335 days:
The 1,335 Days
17 Daniel 12:12 says: “Happy is the one who is keeping in expectation and who arrives at the one thousand three hundred and thirty-five days!” These 1,335 days, or three years, eight and a half months, evidently began at the end of the previous period. Counting from September 1922, this brings us to the late spring (Northern Hemisphere) of 1926. What happened during those 1,335 days?
18 Despite the landmark nature of events in 1922, evidently some still looked longingly to the past. The Studies in the Scriptures, authored by C. T. Russell, were still basic study material. Further, the widely circulated booklet Millions Now Living Will Never Die presented the view that in 1925, God’s purposes regarding the restoring of the earth to Paradise and the resurrecting of the faithful ones of old would begin to be fulfilled. The endurance of the anointed seemed to be nearly completed. Nevertheless, some associated with the Bible Students did not feel impelled to share the good news with others.
19 As the 1,335 days progressed, all of this changed. To strengthen the brothers, regular group studies of The Watch Tower were organized. Field service was stressed. Beginning in May 1923, everyone was invited to share in field service on the first Tuesday of every month, and time was set aside during the midweek congregation meeting to encourage them in this work. In August 1923, at an assembly in Los Angeles, California, U.S.A., it was shown that Jesus’ parable of the sheep and the goats would be fulfilled before the Millennial Reign. (Matthew 25:31-40) The year 1924 saw the inauguration of radio station WBBR, which was used to broadcast the good news over the airwaves. The article “Birth of the Nation” in the March 1, 1925, issue of The Watch Tower gave an adjusted understanding of Revelation chapter 12. Finally, faithful Christians could properly understand the tumultuous events of 1914-19.
20 The year 1925 came to its conclusion, but the end was not yet! Ever since the 1870’s, Bible Students had been serving with a date in mind—first 1914, then 1925. Now, they realized that they must serve for as long as Jehovah wishes. The January 1, 1926, issue of The Watch Tower carried the landmark article “Who Will Honor Jehovah?” highlighting as never before the importance of God’s name. And finally, in May 1926 at the London, England, convention, a resolution was adopted entitled “A Testimony to the Rulers of the World.” This forthrightly proclaimed the truth about God’s Kingdom and the coming destruction of Satan’s world. At the same convention, the hard-hitting book Deliverance was released, becoming the first of a series to replace Studies in the Scriptures. God’s people were now looking forward, not backward. The 1,335 days were concluded.
21 Some were unwilling to adjust to these developments, but those who endured were truly happy. Moreover, as we look back on the fulfillment of these prophetic time periods, we too are happy because our confidence is strengthened that the small body of anointed Christians who lived through those times really is the faithful and discreet slave. In the years since then, Jehovah’s organization has expanded enormously, but the faithful and discreet slave is still at its center, guiding it. How thrilling, then, to know that for the anointed and the other sheep, still more happiness is in store! This will be seen as we consider another of Daniel’s prophecies."
(Wathtower 93 11/1 p. 11-12)
So this went from the second coming in 1874 to a vauge "happiness" experienced by members by 1926 with the release of a book. Would the Bible bother to prophesy about keeping in expectation of the '1335 days' if all it amounted to was a publication released by the WTS?