Go to nearest hdfc bank. Tell them you want to open savings account with preferred banking. They might downgrade if you dont maintain required balance..
Technically, the premium account you open with 5 lakhs will not be a 0 MAB..
But what you can do is open a classic account with 5 lakhs, most likely it will not be downgraded if you maintain some decent balance once a while , preferably at the end of a financial quarter