No. They turned that corner when they published two complete WT articles (Oct/Nov 2011) defending the 607 BC date (which is indefensable). They knew that 607 is the biggest bone of contention in their chronology and surely there was much round table discussion about what to do. Their decision was not just to hang onto it but to take it front and center and face it head on with their Oct & Nov "expert" (Rolf Furuli) explanation. The articles APPEARED to have much historical backing. Few JWs would ever begin to attempt to muddle through it all to confirm or deny anything in them. "The Society said it, so I believe it." You gotta trust them over any "worldly" historian [who is controled by Satan].
First of all, they don't need to change it for most R&F JWs. They have hidden the 607/1914 in an Appendix in the back of the newest Study Book, so most new converts will never even be faced with a serious discussion about it and most JWs won't have to go through it each time the get to that point in the book. It's just covered over. They will continue to keep this doctrine on the downlow. 2 Tim. 3:1-13 will be the cornerstone scripture to be connected to WWI as evidence of their prophecy of 1914 being confirmed.
Second, they will likely start mentioning Noah's 120 years of preaching more frequently. That will give them another 20 years easily, without much fanfare or any New Lite required. Yep, ole Noah didn't give up after just 100 years and only he and his family members got the boat ride to salvation. What if he would have given up after 100 years?
After the 1975 fiasco, most JWs hung in there for another 20 years before the WT had to change the "generation" doctrine in 1995. And most of them still hung in there after that bomb was dropped, although it appears to be the biggest cause of an exodus in recent times. So, I suspect we will see that most of the R&F hangs in for another 20 years waiting for their Ark to sail.