The situation at Kilmarnock continues to shift uncomfortably.

The quiet resentment which had long persisted between supporters and Michael Johnston, the Rugby Park club's chairman, found its voice again following the sacking last week of Kenny Shiels as manager, and the re-emergence of Marie Macklin has increased the level of agitation as the Ayrshire club becomes gripped by civil war.

Macklin, a local businesswoman and chief executive of property development and investment firm Klin Group, had been on the periphery of the club since registering an interest in taking over at the start of last season, although she has since taken centre stage as the fans strive for regime change.

At an annual general meeting of the Kilmarnock Football Club Supporters Association (KFCSA) on Saturday, a statement from Macklin was read out which intimated her continued interest in taking control at Rugby Park and she has already been bestowed the role of champion among supporters following a series of jousts with Johnston. Many of those have been conducted from her Twitter page – Macklin yesterday urging Johnston to join her in a public meeting with supporters to outline their respective business plans for Kilmarnock, having earlier stated that she has a strategy to reduce the club's debt and encourage fan ownership. She also seemed to criticise Johnston for not using social media to better engage with fans but, given the manner in which he has come to be reviled, that would simply become #awkward.

The enmity between Johnston and Macklin has been titillating for supporters, as will be the manner in which she stood up to a club statement which sought to discredit her intentions during those discussions with Johnston last year. In it were claims that Macklin planned to demolish Rugby Park and reduce the club to the role of tenant at a new facility at the Johnnie Walker site, paying annual rent of a "significant six-figure sum". It also suggested £80 million of third-party funding would have been required – increasing the club's debt – and that such an intention was "lacking in credibility- and lacking in vision".

The distrust in which Johnston is now held – the KFCSA's agm included tentative plans to arrange "constant protests" outside his house – will leave many supporters wary of the content of that statement, while others will probably be assuaged by the indignation of Macklin's riposte; accusing Johnston of "playing divide and rule" and rejecting the suggestion that she would decamp the club from its current home were she to assume control. "I don't play games and I am not having my credit ability questioned by a man who has run a club into the ground and has no credit ability," she said on Twitter. "Needless to say it's with my solicitors, MacRoberts Glasgow, where Mr Johnston met my representative! Today's action [the club statement] is by a desperate man trying to cling on to power."

Cal ls for Johnston to be replaced have also become intriguing background noise to the club's attempts to appoint a new manager. Kilmarnock were last night granted permission to discuss the post with David Unsworth, who has been working as assistant manager at Sheffield United after spells as caretaker at Preston North End, and have already interviewed Henning Berg and Allan Johnston, the Queen of the South manager.

A chairman is often allowed to treat patiently the recruitment of a manager in post-season, but Johnston will be wary of being forced out before the process is completed. He had removed Shiels as the Northern Irishman's critique of referees and the Scottish Football Association's disciplinary process last season was making Kilmarnock's relationship with the governing body increasingly fractious, although it was that act which provoked the club's fanbase to mobilise against him in the first place.

Perhaps conscious of the affinity which is still shared between the fans and their deposed manager – despite a few uninspiring results at the tail end of last season which led Kilmarnock to surrender a place in the top six – Macklin also reiterated yesterday her preference to reinstate Shiels were she to be successful in wresting control of the club from its current chairman. It would seem a pertinent consideration for any prospective manager and it is likely Berg and Johnston sought clarification during their interviews.

The Queens manager – who would reportedly cost £30,000 in compensation were he to leave Palmerston after signing a new one-year contract in April – has since returned to a family holiday in Spain after meeting Johnston on Friday but Herald Sport understands the 39-year-old is not desperately seeking a way out of the Dumfries club. The warring at Rugby Park may yet convince him that his blooming career would struggle to flower in the Ayrshire atmosphere.

It has, though, still proven fertile for recrimination, as the board voiced disquiet over supporters' confirmation of their decision to try to force Johnston out of the club. Yesterday's statement concluded with the assertion that the KFCSA were acting "contrary to the sole objective of the association in terms of its constitution: 'To promote the support of Kilmarnock Football Club'," but such a comment will only further isolate Johnston.

The situation will continue to shift this week and it may yet result in Johnston being unseated.