The WT is setting themselves up for another fall with this one. I thought the overlap idea had them off the hook, but no, now they have tied a definite time period to their prophecies again . They never learn.
The point is that the intent of the overlap was NEVER to give themselves decades or even hundreds of years. They quickly realised that the original article was ambiguous enough for there to be confusion and they have tried on several occasions to readjust things. I have sat through 3 talks at a DC and two CAs where this has been discussed. The one at Brighton DC was handled by a Bethel speaker and he was absolutely clear that the ones in the latter overlap would be advancing in years (around their 60s) now. They have also revisited this in the WT.
I would agree this might leave 30 or even more years at the far extent but the implication was clear. Don't think 30 years - think ALOT less.
I disagree that this is a new understanding of the generation (yet again). This is damage limitation on their crazy, madcap and completely illogical explanation from 2010.
I do agree that they never learn. They just know not enough people will follow their gut and leave.