Fitch upgraded Vistra's longterm issuer default rating to BBB, citing the company's improved business profile, strong credit metrics, supportive capital allocation, and improving market fundamentals. "Fitch's recent upgrade, together with S&P's action in December, reflects the consistent execution of our strategy and our continued focus on balance sheet strength," said Jim Burke, President and Chief Executive Officer of Vistra. "We believe achieving investmentgrade ratings positions the company well to main ...