UK network operator KCOM has announced the departure of its CEO Tim Shaw.

The Hull-based company confirmed Shaw has left the business after six and a half years, three of which were as CEO.

KCOM CFO Richard Schäfer is in charge of the company on an interim basis, while the company searches for Shaw's successor.

No reason was given for Shaw's departure by KCOM.

The company noted that under Shaw's leadership, KCOM completed the first phase of its network expansion into new towns and villages - crossing the Humber Bridge into North Lincolnshire for the first time in its history.

During his tenure, the company passed the 60 percent milestone of migration of customers from legacy copper network to future-proof full fiber.

Shaw has also overseen the company's sale of its national business.

"Over the past four years, KCOM has been through some remarkable change. I’m immensely proud of the way the team has focused relentlessly on customer experience, embraced innovation, and taken connectivity to even more homes in the region," Shaw said. "KCOM is an iconic brand, and leading the business through its 120th anniversary last year was one of the great privileges of my role.”

Hull stranglehold has been challenged

KCOM has long held a monopoly in its home city of Hull, and is the only city in the UK not served by Openreach's network, after KCOM refused to merge with other regional providers during the formation of the former telecoms monopoly. Notably, the city's telephone boxes are even a different color.

Founded in 1904 as Kingston Communications, KCOM has seen its dominance in the region challenged in recent years by several rival full-fiber network providers, also known as altnets. CityFibre, Connexin, Grain, and MS3 Networks are some of the altnets building out rival networks in the city.

In 2015, KCOM sold most of its fiber network to CityFibre for £90m ($112m) in a cash sale.

The acquisition covered 1,100 km of duct and fiber cables across 24 UK cities, plus another 1,100 km of national long-distance networks that connect these cities to major data center locations across the UK.

KCOM owner Macquarie owns other infrastructure assets in the country, including Thames Water, which is on the brink of collapse. Macquarie has faced scrutiny over its ownership of the utility company, after loading it up with debt.

Macquarie was said to be considering a sale of the business last year.