I was searching both the wiki and the forums and RFC's pearls to try to find this but I think I might have missed something.
Do we know the 'upper' age rages for the various generations of prolong? IE what the oldest you can be before receiving 2nd or 3rd gen would be? If I remember right mid twenties are the cut-off date for 1st Gen but I haven't been able to find any info on 2nd or 3rd.