Have Jehovah's Witnesses indicated the upper limit for "overlapping generations"? As I understand things the JWs teach that based on references to "this generation" in the gospels the end of the world must happen within "the generation" of those alive in 1914 (when the JW organization was founded, I believe).

However, this has been redefined as the lifespan of two generations that intersect.

So my question is, do the JWs deduce that the end of the world must occur by a certain date? For example, if the end of the world does not happen before 2050 then has the overlapping generations theory failed? IE: At what point will the overlapping generations solution be abandoned? At the time of this writing it has been 104 years since 1914. Do they say that when Jesus said "this generation shall not pass away until all these things are fulfilled" he meant:


one generation = two overlapping generations
two overlapping generations must be &lt;= two generations
in scripture a generation seems to be 40 years (because it took 40 years to kill off the generation that left Egypt): 



  [Psa 95:10 KJV] 10 Forty years long was I grieved with [this] generation, and said, It [is] a people that do err in their heart, and they have not known my ways:


It was about 40 years from when Jesus said "upon this generation shall come wrath" until the destruction of the temple, Jerusalem and over a million Jews.

So it seems that:


a generation is 40 years
two generations is 80 years
two overlapping generations is &lt;= 80 years


So their math is different. What is the math they are doing to come up with their still-future upper date and what is that date? (I want to put "repenting" on my calendar for the day before)!
No, Jehovah's Witnesses haven't assigned an upper limit.

This video, "David H. Splane: Close to the End of This System of Things" (last viewed in Kingdom Halls of Jehovah's Witnesses in March 2018), is the most up to date explanation by Jehovah's Witnesses of "this generation". Concerning when the end of this time period is, we don't know, nor is it any of our concern, because Jesus said it won't come to an end. The video does, however, list some people which can be used as reference points for discerning that "this generation" hasn't yet passed away. All of those currently on the Governing Body are among the ones which were anointed contemporaries with anointed ones who saw the sign of Jesus' coming in 1914.

The main reason JWs care about this information is because it strengthens our faith such that we can continue to live our lives as Jesus said to do: "Keep on the watch, therefore, because you do not know on what day your Lord is coming."

Therefore, knowing that Jesus will come soon to restore the earth to a paradise gives us comfort and hope to continue enduring this system of things and to have added motivation to repent now and live our lives as Jesus commanded.