head the bill
To be the featured person in an event. Two professors from New York University are heading the bill at the conference on climate change this weekend. Up until now he's only been a supporting act, but he's going to head the bill for the first time next Saturday.
top the bill
To be the featured person in an event. Two professors from New York University are topping the bill at the conference on climate change this weekend. Up until now he's only been a supporting act, but he's going to top the bill for the first time next Saturday.