SINGAPORE - An Iranian supertanker carrying stored oil that set sail last week after sitting in Iranian waters for months because of international sanctions has changed its destination to Shanghai from Singapore, shipping data on Thomson Reuters Eikon showed on Thursday. However, Shanghai was unlikely to be the tanker’s final destination as Very Large Crude Carriers (VLCCs) cannot dock at the port, trade sources said. The fully laden VLCC Starla, operated by Iran’s top tanker group, NITC, was the first vessel storing crude offshore to sail after Tehran reached a nuclear deal with world powers last week. The tanker, now off Sri Lanka, is due to reach Shanghai on Aug. 6, the data showed. Sanctions on Iran restricted the OPEC producer’s ability to export, forcing it to store excess crude on tankers. Brent crude has fallen about 4 percent since the deal due to worries about the impact of a prompt release of the estimated 40 to 50 million barrels of Iranian crude and condensate from floating storage.