Credit Union Australia, the country's largest mutual ADI, plans "a more comprehensive overview" of rules that inhibit its demutualisation", the board disclosed in the notice for its annual meeting to be held next month."The credit union sector is experiencing a period of unprecedented change. Where necessary, your board believes CUA needs to be able to respond to those changes," CUA wrote in an explanation to members.Brisbane-based CUA said it was "committed to retaining CUA's current mutual structure [but] proposes that members maintain the current demutualisation rules for a further period of only one year."Only four credit unions have demutualised in the last 20 years, two of them disappearing as customer lists for regional banks and two listing on the Australian Securities Exchange.CUA may not be the only entity weighing this option.Robert Brunner, the chair of Circle Credit Union, based in Melbourne's west, wrote in its annual report that "the board is currently considering an opportunity that would result in a significant change to the credit union's business model."This could mean a merger with another credit union, which has been flagged as one option."We are still working with several like-minded credit unions to explore ideas to effectively address our current and foreseeable challenges, and provide a better long-term future," he wrote.However, at least one mutual is adamant that demutualisation is not on the horizon.Members of Hume Building Society voted last week to support a change in status to a mutual bank. This will come into force from July.Stuart Gilchrist, chair of the board of Hume, said in a statement on its website that "the question was asked [at last week's member meeting] if this was the first step towards demutualisation and a listing on the stock exchange."Gilchrist said: "There has been no such discussion around the board or executive tables about such a move and mutuality is a core principle for Hume."The Australian Prudential Regulation Authority, meanwhile, is fostering efforts by credit unions to develop a more diverse customer base.APRA said on Friday that it proposed to allow mutuals to issue hybrid capital securities that include triggers that can convert to "mutual equity interests."Mutual equity interest would only arise, APRA said, if loss absorption or non-viability events were triggered.APRA will tolerate mutual equity interests on which dividends are capped, and on which the holders do not qualify for an equal interest in the surplus on wind up.The Customer Owned Banking Association (COBA) said the APRA proposal "will restore the ability of the customer owned banking sector to continue to raise alternative forms of capital to retained earnings, an ability that was lost when the Basel III capital standards came into effect on 1 January this year."Mark Degotardi, head of public affairs at COBA, said in a statement: "Our sector is very strongly capitalised and will always rely on retained earnings as its primary source of regulatory capital.""COBA members are strongly committed to retaining their highly successful, customer-focused model but they also need additional capacity to raise capital when they need to