(Bloomberg) UBS Group AG raised its recommendation on a key Chinese stock index to overweight in a rare upgrade call this year, underscoring the tentative optimism that the market is finally on the mend.Most Read from BloombergTrump Has Only $6.8 Million for Legal Fees With Trial UnderwayRay Dalio’s Famous Trade Is Sputtering, Investors BailingStocks Climb as US Earnings Kick Into High Gear: Markets WrapRussians Transform Dubai as They Flee Putin’s War: Photo EssaySea Billionaire’s Wife to Bu