The GB still believes in 1914 they wouldn't be putting out talks and publications if they didn't.
Why you may ask ?
Assume it as a subjective belief but a very important one for the organization.
Like their predecessors before them, they have been mentally indoctrinated with this bogus doctrine themselves.
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Of course people with slightly of a bit of critical thinking will realize that nothing has happen like the WTS. said it would in the past 100 years since 1914.
What will they say in time when numerous generations have passed on from that year ?,
My guess they will just say it was just human error, we have received new light now.
As others have said since they probably know it might be a failed doctrine, so from that they most likely will not bring it very much from now on.