Telstra announced its CFO Robyn Denholm is stepping down to become chairman of the board at electric car maker Tesla a little over a month after taking on the role at Australia’s largest mobile operator.

Although the Tesla appointment begins on 13 November, Denholm (pictured, left) will see out a six-month notice period with Telstra, meaning she will leave the company on 6 May 2019.

Telstra CEO Andy Penn said in a statement: “We are sorry to see Robyn leave Telstra. We know that it has become increasingly difficult to balance her responsibilities as Telstra CFO with the increased activity of the Tesla board,” Penn said.

She joined Telstra in January 2017 as COO and has been CFO since 1 October.

“We are undertaking a search for a new CFO and will provide an update on a replacement appointment as soon as possible,” Penn said.

In a related statement from Tesla, Denholm said she will work closely with company founder and former chairman Elon Musk to “achieve sustainable profitability and drive long-term shareholder value”.

Musk said Denholm “has extensive experience in both the tech and auto industries” gained in similar roles with companies including Juniper Networks, Sun Microsystems and Toyota.

The company founder last month agreed to relinquish his chairman role following allegations of financial fraud in the US, BBC News reported.