Leon Black, the Wall Street billionaire who was the main client of the disgraced financier Jeffrey Epstein for the last decade of his life, is stepping down as chief executive of Apollo Global Management, several months ahead of schedule.Mr. Black also will give up the chairmanship of the private equity firm, which he helped found roughly three decades ago, the firm said in a statement on Monday. Jay Clayton, the former Securities and Exchange Commission chairman who recently joined the firm as an independent director, will take his place.The firm had said in January that he would step …
