In order to cleanly and simply add start and stop dates to a Feature (Epic in our view) you have to enable Planning ("Enable capacity planning and time tracking") for those fields to show up on the Feature page (Features > Board > detail of a feature). That then also enabled the capacity planning on the Epic Board. We don't need that, or want it right now. So then you have to either live with a red line griping about capacity or enter dummy values (999d) in which case it then shows you a dummy bar about capacity which looks silly. just separate out this check box into Enable Dates, Enable Capacity Planning.
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