I studied with one of the "anointed" and so was privy to her ideas and reasonings on certain subjects. She kept count on the yearly numbers and paid unbelievable attention to them. As there were 4, yes 4, others in our congregation, there was plenty of talk about this subject.
She was positive that there would always be a number of the F&DS class on earth to live through Armageddon, no matter when it occured. There HAD to be to lead us all into the new system. There wouldn't be some 8000, but there would be a fair share.
The reason the numbers went down and back up was because there would obviously be ones who fell away and Jehovah was actively anointing newer and younger ones all the time. She was in her early 40's. The others were all mid 30's to late 50's, all sisters. My last year with that cong., 2 of them left the truth which proved her point.
Then a mutual friend of ours, his younger brother, maybe 25ish, got the calling. They had been raised in the truth, but because of abusive parents left at an early age. His brother had been back in and baptised less time than me! I was like what the hell, but you can't question it. When you know it, you know it. She wrote hom letters to "congradulate" him and see how he related to things. He convinced her, I never met him.
So, there you go...from those who KNOW...Jehovah will always be anointing younger and younger ones therefore the numbers will never go to zero. Sounds pretty reasonable, eh?