New Epic self-link not available on existing epics

4.3 introduced links on the Epic that are available if the Epic has a self-label with its own key. This is confusing for existing data because no self-label exists. JC has pointed out that new cards created from that Epic will fix the data (add a label to the Epic). However, this doesn't alleviate the support issues we face with users.

It would be nice if we designated an Epic field and Epic issue type in our template and then a background process added missing labels for that type and field.