Well the GB heads have already rewrote the words in the bible by saying generation(s) instead of generation, so whats stopping them of doing more revisions or twisting and manipulation of scriptures ?
For example they could say all generations from 1914 forward who preach Jesus's new Kingdom are being righteous and loyal to Jehovah.
I would even guess they would drop 1914 altogether and just say we are true loyal preachers of god's will and purpose in proclaiming god's new kingdom to come... etc.
New light is a coming, new understanding through god's holy spirit and guidance as they have proclaimed
Old light such as 1914 will be cast off