Mar.7 (GMM) As Honda this week wrapped up its track preparations for the 2008 season with a private test session at Jerez, it emerged that two leading members of the beleaguered Japanese team are set to depart.

Although scheduled to attend the Australian grand prix next weekend, Yasuhiro Wada - the chairman and general manager of Honda's motor sports division - is reportedly vacating his post at the end of March.

Meanwhile, the team's chief designer Kevin Taylor is understood to have already left.

Wada, en route to the PR and media division in Japan, is to be replaced by Keita Muramatsu, the manufacturer confirmed, insisting that the change is part of the company's normal philosophy about staff rotation.

Following an apparently uncompetitive winter with its new RA108 single seater, Honda tested its final Melbourne-spec package for the first time during a three-day exclusive test at Jerez this week.

"I was pleased that we have made a step forward in terms of performance," said British driver Jenson Button.

"We are realistic about our expectations for the first few races and know that we still have a long way to go."

It also emerged that Red Bull Racing on Thursday completed a short test with the RB4 car on the short circuit at Silverstone (UK).