Due to a new agreement between WhatsApp and Google, WhatsApp backup will no longer count against Google Drive Storage. However Any WhatsApp Backups that have not been updated in more than a year will automatically be remove from Storage.
Starting November 12, 2018. WhatsApp backup will no longer available on Google Drive. To Avoid The loss of backups we recommend you to manually backup your data (says WhatsApp).
How To Manually Backup Data:
It doesn’t mean that all your WhatsApp backup on Google Drive will delete. WhatsApp Users need to manually backup their Data on Google Drive Before November 12, 2018.
Will My Google Data Deleted Automatically ?
No. WhatsApp backups on Google Drive will not get deleted automatically, given you update manually before November 12. Users who wish to refresh their existing backup will have update before October 30 this year. This can be done from the Settings menu of WhatsApp app.