SGoE: Shortly before the GT they will be taken to heaven for their reward along with all others of the anointed. After that there will only be OS/GC left on earth. so:
The great crowd is really the generation that Jesus was speaking about when he said the the generation would not pass away until all these things, ( GT, Armageddon Judgement of goats) has happened. and,
while, according to this wt theory, the anointed GB can not be of the GC, it definitely is not the generation, --save yourself the overlap.
unless of course the GC really ends up in the heavy heavenly temple, Naos.