Oh crap, I just noticed that @awscloud versioning duplicates the file even if the file is exactly the same. DOH! https://t.co/xLDGOJryO0— Kai Hendry (@kaihendry) April 22, 2016
HOWEVER If you use sync then the file will not be replaced, unless it has changed!
aws --profile jewel s3 sync bar s3://s3test.jptdev.com/
Unfortunately there is no way to be notified if a file has been replaced AFAICT!
There is a S3 event RRSObjectLost which is quite interesting.