As soon as one part of the content is about official business, then the whole content is a public record

Keywords: create and capture , examples , keep and destroy , manage records , email , private accounts , public records , social media

This is why we recommend you keep your personal, private, constituent, electorate, party-political, divisional records or any other non-public record information separate from your business records – wherever possible – don’t mix them.  Once they’re mixed, it’s almost impossible to undo. Once you’ve added the egg to the mixture – you can’t take it out again!

https://grkblog.archives.qld.gov.au/2020/07/14/mixing-your-records-dont-do-it