aws s3 sync --delete removed some new files.
aws s3 sync --delete
For example:
There is a file in the bucket - S3://my-bucket/images/1.jpg
S3://my-bucket/images/1.jpg
Then
For the new s3cmd you can use the option --delete-removed to removed extra files in the destination, that are not present the source.
s3cmd
--delete-removed