Comment 1 for bug 405086

Curtis Hovey (sinzui) wrote :

They are ordered by name. The name of series and milestones (and the version of a release) are sorted using the sorted-dotted-number rules use by debian.

The reason we do not use date is that not every milestone has a date expected, many are not timeboxed. Since the milestone name is the release version, and releases are numbered in sequences, we use the milestone name to sort.