Interesting analysis , Yadda.
My view - I’m taking the assumption as backed up in Franz's books that the WTS leaders actually believe what they say is true , rather than the common “apostate” view that they know that it isn’t true & are cynically manipulating or adjusting their ideas to maintain their position & keep most of the R&F on board & on message.
On that basis , I reckon that the 1914 teaching is essentially safe in the present form till well into the 21 st century. By linking the “Last days” to Noah’s 120 year timescale (WT 15th Dec 2003 p15) they are “safe” till at least 2034.
More and more elders and MS's are resigning their positions and duties, meeting attendance is dropping quickly, and general apathy and atrophy is setting in. This downward trend is going to force them to re-think the whole 1914 creed in the years ahead.
This is certainly true among some (me included!) , but I also see great enthusiasm among many JWs. In the UK , there are consistent all-time peaks of regular pioneers - many JWs are increasingly zealous for foreign language congs. Also fast growth in the 3rd world & amongst immigrant communities. Year-on-year 3% growth. And anyway , the GB & most Bethelites are in an ivory tower situation - immune from & generally unaware of any criticism from the r&f. The only feedback they get are from Bethel reps who are placemen relying on their position on the GB - they generally only tell them what they want to hear , even if they secretly harbour doubts.