I purchased MYOB for Mac in 1996, and upgraded to Mamut Accountedge 2008. There were some file verification issues following the splitting up of the UK vs Australian MYOB business but to their credit Mamut eventually took on the legacy server. MYOB (2008) still works reliably on Mac OS 10.8.5 and iMac 2007 and is free of any running costs.
The shift towards making tax digital means the MYOB software will not be compliant. I considered moving to MoneyWorks but decided it would be better to buy into the annual Mamut support contract which would provide the latest version of Accountedge and add this capability, releasing the legacy hardware. However if the roadmap for their software is a dead end it looks like I have dodged a bullet.
Thank you to The Register for this timely news... I now know my MYOB-2008 is not going to survive another incarnation and I will be looking for a fresh start with another accounts package. Thank you MYOB, it's been emotional.