The Surin Farang Forum has a section on Visa and Extension requirements which members find very useful. Please feel free to read the relevant pages by visiting surinfarang.com/forum/forums/visa-immigration-issues.27/ Better still, we would encourage those with interests (far beyond mere food) to apply for membership which will allow access (on approval) to the 'members only' sections too:
I believe that you and I have the same Non-0 Multi based on marriage to a Thai. They are both valid until 14 January 2021, but we must leave Thailand (border hop) by 14 April 2020. As you are in Australia now, your next step will be to re-enter Thailand when circumstances allow and before 14 Jan next year. Your visa doesn't expire until the 12 months is up, subject to leaving the country every 90 days.. Your NEXT 90 days will begin when you return from Australia, and you will then need to border hop again 90 days after that.