Define time for analysis "evaluate" button to make debugging faster

Currently, the evaluate button can run your evaluation at the current timestamp and the last scheduled time. It would be really helpful to key in a 3rd timestamp to diagnose edge cases. The current workaround involves putting dummy variables in to force analysis at a specific time or previewing the results for each programming iteration. For a complex analysis this could involve 10's or 100's of iterations to debug all edge cases.