Immigration in Japan was accepted applications for renewal of status of residence for those who will expire in March-July, within three months from the expiration date.
The reason was to prevent the spread of COVID-19.
However, there is no special case from August.
If you will expire your period of VISA after August 2020, please apply for renewal or change by the expiration date of your period of stay.
If you cannot apply for renewal or change by the expiration date of your period of stay, you will lose your status of residence and will be staying illegally.