(Sharecast News) - British oil and gas firm Hurricane Energy completed the start-up phase of its Aoka Mizu floating production storage and offloading unit with a 72-hour production test.Hurricane told investors on Thursday that combined flow from both wells during the test period reached and maintained its planned production rate of 20,000 barrels of oil per day, marking the contractual provisional acceptance of the Lancaster field asset.The AIM-listed company now anticipates a gradual ramp-up in facilities availability over the first six months of production towards long term operating efficiency of 85%.Hurricane also restated its existing guidance for average production rates of 9,000 bopd for the coming quarter and 13,000 bopd for the half.Chief executive Dr Robert Trice said: "I am delighted to announce that first oil has been achieved and that the Lancaster field is now on production, beginning the phased development of Hurricane's considerable resources on the Rona Ridge."Looking forward, Trice noted that as much as 12-months worth of stable production would be required in order to provide Hurricane with "a clear view of the reservoir" and enable the firm to plan for the associated "full-field development scenario".As of 0825 BST, Hurricane shares had picked up 2.71% to 60.65p after notching-up an intraday high at 64.50p.