Hello,
we have noted that sometimes webpack generates the same hash for a chunk, even if the file content has been changed.

Due to this, changes sometimes are not propagated, we experience an error similar to #959 and we're forced to clear the cache/CDN to make the things work.

We are using the following plugins in the given order:

ExtractTextPlugin
CommonsChunkPlugin
OccurenceOrderPlugin
WebpackAssetsMapPlugin //custom plugin, writes the json stats file to the disk
DeduplePlugin
UglifyJsPlugin

Let me know if you need further details,
V.