I believe marking the lifespan of the soul as one Great Sidereal Year is quite optimistic. If we take the whole cycle of an incarnation to be an average of 144 years, as some suggest, that would only allow about 180 incarnations (c (2160 x 12 = 25,920) / 144) , to learn everything we have to learn and develop all the potentialities of the vehicle.
Some say the total is in the seven-figure range. Some just say, it's 7 x 12 x a zillion and leave it at that.