Third-generation mobile operator Hutchison 3G is believed to have put the firm on notice after news that four of Firefly's six directors had left amid a boardroom row.
A Hutchison spokesman refused to comment on the matter, but it is understood Firefly is currently working out its contract just nine months after first winning the account.
Last week saw the surprise departures of Firefly deputy MD David Hargreaves, director of 10 years Kieran Moore and directors Annabel Abbs and Ricky Merry, as reported on prweek.com.
PRWeek understands that an attempt by the departing directors to take charge of the agency failed.
Founder and MD Claire Walker said: 'The issue was one of management style and who should control the business. I have no wish to give up my position as managing director at this company.'
According to an e-mail obtained by PRWeek, another client said the departure of the directors came as a result of a 'disagreement at board level', which saw Moore and Merry placed on leave last month.
Walker, with husband and director Mark Mellor, remain in charge of the agency and have bought out the 50% of the firm they did not already own.
She confirmed that both Moore and IT director Merry had already left, and that Hargreaves and Abbs were working out their notice. All four staff have signed confidentiality agreements and were unable to comment.
Walker added that former Weber Shandwick tech chief executive Cathy Pittham is to join as a director. Pittham left WS late last year.
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