Mr. Jones, who also served as Everest's chief operating officer, had been named as the successor to longtime CEO Joseph Taranto in July, with the end of the year set as the time when he would take over the top job.
In a statement Monday, Everest Re's board of directors said that it asked Mr. Taranto to "reconsider his decision to retire," and said he would now stay on as CEO of the Bermuda-based company through 2012.
"I am dedicated and energized to continue to lead the Company forward," Mr. Taranto said in the statement. He also said he wished Jones "the very best."