Former T-Mobile US CEO John Legere (pictured) quit the operator’s board more than a month earlier than expected, citing the pursuit of other options.

In a stock market notice filed on 24 April, T-Mobile said the executive had stepped down effectively immediately, having previously intended to stay on until 4 June.

Legere ceased to be CEO of the company at the start of April on the completion of the operator’s long-awaited merger with rival Sprint.

On first announcing his departure as CEO, Legere had been expected to remain in charge until the end of April but also left that role early, stating it made more sense for incoming chief Mike Sievert to take the reins on the day the merger completed.

In the latest filing, the company stated Legere was leaving to pursue other options and was not resigning due to any disagreements with its management or board.

The development brings to an end the outspoken executive’s seven-and-a-half-year association with T-Mobile. He was appointed CEO in September 2012 and took a place on its board at the end of April 2013.

Prior to joining the operator, he led telecoms and technology networking company Global Crossing, having previously worked at Dell along with a lengthy stint in various roles at AT&T.