Others have suggested that Bloomberg’s plan would be to resign (ostensibly for health reasons). He could make a deal with Hillary—let him be President for a few months or even a year, then she could take over. And he would seek her approval for any important appointments he made. She could take the time as Vice President to replenish the Clinton Foundation coffers Biden-style.
Bloomberg is mostly just trying to keep his name in the news. We’ll get more leaks like this from his camp.