I have not read that magazine but it does not seem from the quote that the Society is setting a new date outright. It seems they are trying to instill some hope and energy into the brothers.
If though they are trying to point to a date 2034 is too far away for the core workers the vast majority of the long time faithful brothers to look forward to. This would be more discouraging than encouraging to them I think. The Society's younger ones need the older mature ones in their forties and fifties to help them to keep going. If the Society discourages the baby boomers who have waited for so long and who have witnessed the passing of the previous generations I think it would be catastrophic for the Organization.
I find it hard to understand why they act the way they do, since they even act without reason or common sense many times.
Sabrina