I will even say that he will jump to 3b cuz he jumped from 1×× to 3xx even though luffy was 500 ?! REMEMBER dressrosa bountie ?!
So he if luffy become 5b after elbaf which is valid since he didnt even got what he deserved in wano + egghead
It's not far fetched to say zolo will be 3b similar to dressrosa.
Cuz this pattern (
1,111,000,000 / 3,000,000,000 - Post Wano
120,000,000 / 3,000,000,000 - Post Enies Lobby
) is not the absolute pattern.
...
So its up to oda either he follow what u said or even bring something new lol or maybe there's no increase at all only for luffy

Also u may say that the max is 5.5b as pk
But don't think so since luffy will surpass them roger stopped at being pk luffy will go beyond same for his crew.