Effort pertaining to a given Release

Are Actual Effort, Est Effort, Remaining Effort and Projected Effort parameter values in relation to a given Release derived and calculated based on Incidents/Tasks only???

Why doesn't the Est Effort allocated to a Test Case, which is aligned with Release Test Coverage not taken into account when calculating Projected Effort against the Release?  Am I missing something?

We've allocated both Incidents and Test Cases against a Release, yet only the Est Effort allocated against the Incidents are being used in Projected Effort calculations.

Apologies if this is available in later versions of Spira - currently using v3.1