Well, if Democrats win the presidency in 2020 and no legislative action is taken to fix DACA during those 4 years chances are the program would remain in place during that period. Simple arithmetic here. You end up with 6 more years of DACA or 2MoreYears of DACA with the possibility of a fix.

Optionally, if Democrats win the presidency for a second time in a row then they get another opportunity to fix DACA, if it hasn't been fixed yet, or an additional 4 years of DACA for a total of 10 years of DACA protections.

So in recap and hypotetically, there could be a fix for the program during the next 10 years or, worst case scenario, you end-up having DACA for the next 10 years if Democrats take control of the White House in 2020 and 2024.