Most admins want to keep an audit log for more than 90 days without E5/A5/G5 license or any additional add-ons. Now, admins can retrieve the audit log for longer than 90 days and up to one year for all subscriptions.
This feature will help to retain audit logs to support legal obligations, internal and compliance investigations.
https://o365reports.com/2021/07/07/microsoft-365-retrieve-audit-log-for-1-year-for-all-subscriptions/
But Microsoft has not given any announcement regarding this feature. Are you able to retrieve 1 year audit log for your tenant?