China’s accelerated crude stock builds in 2025 may come in handy at the end of this year as global oil flows are being redirected again in the wake of the U.S. sanctions on Russia’s top oil firms. China, the biggest buyer of Russian crude, has a cushion to soften the blow from the sanctions, although it’s unlikely it would halt its imports from Russia. But the stockpiles in China, estimated at between 1.2 billion and 1.3 billion barrels in strategic and commercial reserves, have put a floor under oil prices in…