By Donna Kardos Yesalavich Of DOW JONES NEWSWIRES NEW YORK (Dow Jones)--BP PLC's (BP) U.S. shares fluctuated between small gains and losses Thursday after the U.S. government maintained its projection at mid-August for the completion of a relief well that could stop the oil spill in the Gulf of Mexico. Earlier in the session, BP's American depositary shares had been up, and the stock closed 1.4% higher in London, after a Wall Street Journal story citing company officials said BP is pushing to fix its runaway Gulf oil well by July 27, possibly weeks before the deadline the company has been discussing publicly. The government's reiteration of its mid-August projection threw some cold water on investors' hopes that the well would be complete this month. BP's U.S. shares were down 0.1% to $33.17 in recent trading. The stock is now up 24% from the 14-year intraday low hit last month, although it is also still down more than 45% from its close April 20, when the Deepwater Horizon rig exploded. The action in other markets showed the sentiment toward BP continues to get less pessimistic, although plenty of bears are still present. Options on BP were active in both calls and puts, although there was slightly more volume in calls, which convey the right to buy shares. Meanwhile, the cost to insure against BP defaulting on its debt for five years fell to $423,000 for $10 million of coverage from $436,000 at Wednesday's close, according to Markit, a data provider. Tudor Pickering told clients in a Thursday note: "Late July is possible (barring storm disruptions) as relief well number 1 is ahead of schedule and has successfully located the Macondo well." However, the firm added, "we'd argue that if BP cuts even one single corner just to get something done by its earnings release date, they are playing with fire. So, for those that want a more conservative estimate leave mid-August on your calendar." Investors expressed similar caution. "There's still a very open question with regard to the timing and effectiveness of the relief wells they're drilling right now," said Tom Samuels, managing director at Palantir Investments. "We would love to be optimistic, but I'm not convinced that they're going to be able to pull it off this month." Samuels said his firm doesn't have any BP shares. Calling BP's risks "unquantifiable," he said Palantir is keeping BP out of consideration as a potential investment over the near term. As for those investors who have been buying the stock recently, "there are different entities that have different thresholds for risk," Samuels noted. "It reminds me a lot of companies that were jumping in to invest in the mortgage lenders in 2007 and 2008 thinking they can't get any cheaper than this. Until the risks are at least visible so you can look all the way around them, it's speculation." -By Donna Kardos Yesalavich, Dow Jones Newswires; 212-416-2188; donna.yesalavich@dowjones.com (END) Dow Jones Newswires July 08, 2010 12:58 ET (16:58 GMT)