Comment 5 for bug 194558

A faster connection is about all that can be done, and that is not always an option. There can be connectivity issues between you and launchpad that may resolve themselves.

You could place the file in another public location (http or ftp), then set the filereleaseglob for the series find just the files you want to upload. The product-release-finder runs once a day and looks for files that match the glob. It will match the file name to the milestone and add the file for you.