A Director Penalty Notice is the ATO’s final warning. The 21-day clock starts...
https://www.tumblr.com/brightlyverdantberserker/813988790235463680/what-is-the-simplest-way-to-explain-lockdown-dpns
A Director Penalty Notice is the ATO’s final warning. The 21-day clock starts the moment it is issued, not when you open the mail. If your PAYG, GST, or SGC returns aren’t lodged, you face a lockdown DPN, making you personally liable for the debt