A mooted merger between Australian Military Bank and Central Coast Credit Union has been called off, CCCU announced on Friday.The boards of the two mutual ADIs agreed before Christmas to pursue the merger, with the credit union planning to adopt the name Central Coast Bank.Only a few days ago CCCU notified members of information meetings this week and next. These were cancelled on Friday."Unfortunately due to AMB's intention to upgrade their Banking Software Platform, the commitment necessary to get the software conversion over the line does not allow the aligning of the two organisations possible," Darren Hooper, general manager of CCCU wrote at its website."With such a project, AMB was unable to place a timeframe on when merger implementation planning could commence, leaving the progress of any merger up-in-the-air. "Without any real time commitment a decision was made to cease all merger negotiations," Hooper said.He added that "CCCU's board of directors and management still believe that aligning our credit union with a larger mutual remains the best option."The CCCU board will continue with their strategic direction continuing to investigate such opportunities that are in the best interests of our members."AMB's annual report for 2017 explained to its 53,000 members its "upcoming bank transformation project, where we are overhauling the bank's core IT, internet and mobile banking systems."The mutual bank, which has held that status for a couple of years, could point to "above average banking system growth with total assets of A$1.25 billion, up 10 per cent for the year."CCCU has assets of only $42 million and one of the lowest returns on capital in the banking sector.