According to [AWS documentation](http://docs.aws.amazon.com/AmazonS3/latest/API/sig-v4-authenticating-requests.html):
> Any new regions after January 30, 2014 will support only Signature Version 4 and therefore all requests to those regions must be made with Signature Version 4.
Phabricator only support signature version 2 (https://github.com/phacility/phabricator/blob/master/externals/s3/S3.php#L1820-L1823), so when we upload file to S3 will get error like this:
{F915190}