I just want to know when fine will start on...

Kindly be noted that whoever has his / her visa expired before 1-3-2020, must leave the UAE before 8/18-2020, and no fines shall be imposed. Also, those whose visas expired as of 1-3-2020, their visas will be valid until 31-12-2020, the end of the year. Therefore, your visa expired visa under this category and your visa is still valid.
Finally,please know that we in the legal section are specialized in responding to legal-based inquiries only, and we have no relationship with any government or non-governmental entities