Thinking out loud, are these definitions correct?
Individual varieties/cultivars are permanent, generally registered entities.
Series Names (marketing tools) may be ephemeral, as sales and new developments dictate. They are not necessarily tied to a specific genus or species. They are sometimes, but not always cooked into a cv. name and therefor become permanent.
Mixes and Combos are likely ephemeral and could disappear or be changed in future years, as sales and new developments dictate. These may or may not be part of a Series.
