Your math is off.
If you assume that all licenses sell out right away, you can sell a license for 40.000 dollars making a 38000 dollar profit right away (if you buy during presale)
It will take a long time for all the licenses to sell out. Supply and demand will decide how long it takes to sell out. If few sells you earn a lot per month, if many sells you can sell your license. (withour considering the sps price)