LIVING Lerwick is looking for a new chairman after Gary Bain stepped down from his role at the organisation.
The LHD man said his decision, which came after three other directors also called time on their roles, was for personal reasons.
Vice-chairman Steve Mathieson said it was a "natural turnover" of members and denied the organisation, which aims to promote the town centre and its businesses, was experiencing a "specific exodus" of directors.
Bain said there is "definitely" a positive future ahead for Living Lerwick despite its members only narrowly voting in favour of renewing its town centre business improvement district (BID) for another four years.
"I'm fully supportive of Living Lerwick and I will be helping them as much as I can," the former chairman said on Tuesday.
Mathieson, who will temporarily fill Bain's role, said some directors had left for a fresh start after the first BID came to an end this summer.
"If someone has been doing this for five years, then it's only natural that you would think that maybe other people might want to step in and put their own ideas forward," he said.
"There has been no specific exodus of directors for any one reason, apart from probably the fact that it's a natural break and that it's the end of one contract and the start of the other."
Directors Gemma Jamieson from Specsavers, Frances Richardson of KGQ Hotels and Emma Gibson from the Peerie Shop and Cafe have all stepped down in recent weeks.
Its board currently consists of Mathieson (VisitScotland), Stewart Jamieson (Harry's) and Ben Mullay (Camera Centre).
Living Lerwick hopes that it will be in a position to announce new directors in the coming weeks, some of whom have already been involved in its projects.
On Monday the invitation for tenders for the next Living Lerwick project manager was due to end following the departure of Christena Irvine.
The post will run until 31 August 2021 and it will have an immediate start.
Mathieson said Living Lerwick may extend the recruitment timescale to offer new directors a chance to give their thoughts.
"We've had a certain number of applications into that role that we're looking through at the moment, but it may be the case that we might extend it," he said.
"Unfortunately because it's been half-term, I've been away on holiday and so have some of the other directors. And especially if we have new directors in board, then I think it would be only fair to involve them in that process, as they may have their own specific views on what the project manager should be looking to achieve in that role."
Members of Living Lerwick voted in a ballot in August on whether to extend the BID scheme.
A total of 89 votes were cast, with 49 firms in favour of renewing the BID and 40 against. There are 143 non-domestic properties in the area.
In June, Shetland Islands Council - which has six properties in the area - agreed to vote in favour of keeping the BID, although it signalled its intent to withdraw its £20,000 a year core funding.
The BID covers the area from the Cee & Jays sports shop to the Queen's Hotel, and also includes Lerwick Town Hall and George Robertson's electrical shop on the Hillhead.
Living Lerwick, which has overseen the BID since its first term started in 2013, aims to "create a more vibrant, viable and sustainable town centre".
It brings together local businesses to host events like Shopping Week and Christmas celebrations, while it has also spruced up the appearance of Commercial Street.
But some firms don't feel they have received value for money from the scheme, which requires a compulsory levy to be paid based on the rateable value of their property.
It ranges between £200 to £850 a year, and it is projected to generate £71,050 a year between now and 2021 which will be spent on the BID area.