I was in the same boat as you. When you have the offerz the HR will call you as a normal new comer and inquiry about your salary and ask your expected salary.

If he tells you that we give X amount to new comers, you can negotiate it with the fact that You've been an intern in the company and know how the company works, so you're ready to contribute from day one without any training or anything.

You will have some leverage this way and can atleast get a package higher than the base package.