Good morning Charles.  The Canary team has reviewed the issue.  As you know, the Calculation Server relies on a steady stream of data to accurately run 'periodic' calculations; meaning the calculation will run as scheduled whether one or all of the data points that feed it have successfully made it from the field to the historian.  When the calculation runs prior to the data arriving, obviously the KPI calc is not valid.  The issue lies in not having a way to efficiently rerun all of the calculations and overwrite or version changes in them.  

We would strongly recommend our partner, Flow Software to solve this problem.  They specialize as a KPI calc and management tool that is built for these exact situations.  I have verified with them that they re-run their period KPI calcs on schedule as version any changes.  Additionally, there are a few other benefits that you would pick up from their system as well that Canary does not and will not support in the future.  

I know this may not be the answer you hoped for, but I wanted to be as transparent as possible.  Our roadmap is currently focused on advancing our product in another exciting direction.