Hi,
Thank you for your reply.
For backing up the emails, the command "gyb --email <source-email> --action backup --local-folder <"local-path"> --service-account"
For restore, "gyb --email <group-email> --action restore-group --local-folder <"local-path"> --label-restored backup --service-account --use-admin <admin-email>"
Backup and restore were successful.
But when I open the group, the number of emails showing is less. I am not sure, if the total number of emails in the backup includes sent items, drafts etc. and the restore contains inbox only.
For mailboxes with comparatively less number of emails, it is working fine, But I faced issue with larger mailboxes(more than 10k emails).