Star Sirius
https://en.wikipedia.org/wiki/Historical_brightest_stars
According to the data above, Sirius started to be the brightest star c. 90000 years ago. That is 3 1/2 great years ago, when SIrius was conjunct Capricorn (the great opposition).
AB - RA - HAM happened around the same timeline, as Sirius was still conjunct Capricorn (do not mix up stars/constellations with the zodiac).