SFTP allows users to transfer data over a connection that is secured using the well known Secure Shell (SSH) protocol. SFTP stands for Secure File Transfer Protocol and it relies on SSH.
The bug that failed transfers larger than 2GB has also been dealt with.
If you want to upload, files, themes and plugins you can do so directly through the WordPress admin area. All our WordPress hosting accounts come with WordPress pre-installed, configured and ready to go. Use Cyberduck for Windows or Cyberduck CLI on EC2 and have setup IAM Roles for Amazon EC2 to provide access to S3 from the EC2 instance. Download S3 (Credentials from Instance Metadata) connection profile for preconfigured settings.