no real answer to the questions, since we don't know how many games he will be playing from here to then
If he keeps up his pace that he had now, it would take him circa 72 years (I. e. took him 8 years to get One belt, one belt is 1/10th of Elite belt, so add the remaining 9/10ths )
afaik he sits in rooms most days so lets say he plays all 100 games every day, well then it would take him circa 30 years
and lets not leave out the option that he would have qi doubler enabled from now to then (pretty unreasonable, but this whole shindang is unreasonable) it would take him circa 15 years
I think its fair to say he wont be reaching elite belt by the normal terms.