What are possible backup status in velero?
As I see in Velero code (version: v.1.5.3), the backups can have the following phases:

New
FailedValidation
InProgress
Completed
PartiallyFailed
Failed
Deleting

see: https://github.com/vmware-tanzu/velero/blob/v1.5.3/pkg/apis/velero/v1/backup.go#L195
Restores have these phases:

New
FailedValidation
InProgress
Completed
PartiallyFailed
Failed

see: https://github.com/vmware-tanzu/velero/blob/v1.5.3/pkg/apis/velero/v1/restore.go#L184