Three managers have left Birmingham Museums and Art Gallery (BMAG) as plans to restructure the service are implemented.

Jane Arthur, who was head of collection services, and Isabel Churcher, the head of museums services, have quit. Reyahn King, the masterplan project leader, took up a post as director of art galleries at National Museums Liverpool in August.

A document obtained by Museums Journal outlines how under the restructure, most of the functions of the old posts of head of collection services and head of museums services would be merged into a new post, titled head of collections and operations (deputy).

The role would combine collections management, visitor services, collection care, technical services, workforce development, accreditation and commercial operations.

Rita McLean, the organisation's head of museums and heritage services, said: "This reconfiguration has enabled the creation of a new role which brings together, at a strategic level for the first time, the care of buildings and collections with front-of-house operations."

She added that other senior management posts will be: head of heritage services; head of learning and outreach; head of interpretation and exhibitions; head of projects and development; and planning support manager.

A source said there had been recognition that the service had a "top-heavy management" structure and that Renaissance-funded posts needed to be integrated. They added that staff had to "face the fact that roles change".

It is believed that the management of Birmingham Museum and Art Gallery will be consulting trade unions this month over the restructure's implications.

According to Museums, Libraries and Archives Council (MLA) West Midlands, the restructure is unlikely to affect the museum's phase-one hub status. Jon Finch, chief executive of MLA West Midlands, said: "We have been having conversations with Rita McLean, but the restructuring is still being discussed internally, and we have no details as yet."

Despite Birmingham Museums and Art Gallery's budget rising from £6,503,161 in 2006-07 to £6,761,365 in 2007-08, the museums service is operating a revenue budget deficit and needs to make savings of £350,000.

Patrick Steel

Correction: This article was incorrect in reporting that Isabel Churcher had quit Birmingham Museums Service.