Tony Hayward's chances of getting "his life back" increased this evening as speculation mounted that he could lose his job before the end of the year as the Gulf oil spill crisis continued to rumble on.

Ahead of a vital briefing with financial analysts tomorrow when the BP chief is expected to promise to stick with dividend payments, there was widespread debate about how long he can survive in his job.

"There is no doubt, rightly or wrongly, that there will be management changes at BP," said Alex Stewart at City broker Evolution Securities. "It is better for the company that the company management take as much of the heat as possible and hope that when this problem is over the company can move on."

The Evolution analyst was not the only one speculating on Hayward's future. "It looks increasingly likely that heads will roll and Tony will be in the frame. The longer these things go on, the shakier things look for the company," Dougie Youngson, analyst at Arbuthnot Securities, told Bloomberg Television.

BP is reeling under the impact of almost a third being wiped off its share price since the Deepwater blowout on 20 April. Spill liabilities and claims have been estimated at anywhere between $20bn and $60bn (£14bn and £40bn).

The former head of BP exploration who took the top job in 2007 has sometimes made a bad situation worse. He used social networking platform Facebook to apologise for saying he wanted his life back from the eye of a storm that has kept him so busy since the blowout. He also admitted BP was "not prepared" for the spill, creating a flood of new headlines to the formerly media-averse geologist who has been running the company since the exit of his predecessor, John Browne.

Today the pressure was further increased when rating agency Moody's downgraded BP's credit worthiness to Aa2 from Aa1 and said the company remained "on review" for further reductions reflecting "significant containment, litigation and clean-up costs". Fitch had earlier cut the rating on BP's long-term debt from AA+ to AA citing an estimated annual clean-up cost of $5bn annually.

The company has previously attracted support from investors by promising rising dividend payments. BP has been told by senior US politicians that it should halt all payments to shareholders but Hayward knows such a move could chase away further investment funds which specially focus on high yield "income" providers such as BP.

The wider oil industry has also been hit by the BP spill.The insurance industry, hit by losses estimated at between $1.4bn and $3.5bn (£2.4bn) from the disaster, has been quick to raise its prices by as much as 50%.

Deepwater Horizon is the largest single oil drilling rig loss since the 1988 Piper Alpha platform explosion in the North Sea, which triggered $3.6bn of insured losses (at 2009 value).

In a report on the impact from Deepwater Horizon published today today, credit ratings agency Moody's noted that insured losses would be "significantly" higher if BP, the operator and majority owner of the project, had purchased liability insurance in the commercial market instead of self-insuring its risks through its captive insurer, Jupiter Insurance.

The agency said early reports indicated that insurance premiums for deepwater rigs have jumped by up to 50% since the explosion, while the cost of insuring rigs operating in shallow waters has climbed by 15-25%.

"With the 2010 hurricane season just around the corner, any additional offshore energy losses in the Gulf of Mexico this year could further bolster pricing for offshore energy exposures," the agency warned. "Likewise, we expect offshore energy liability insurance premiums to trend higher, perhaps meaningfully, as insurers and reinsurers take stock of their losses and re-evaluate the complex risks associated with drilling in deep waters."