docs: changelog update for 13.0.x

docs/docs/changelog/v13-0.md

@@ -8,11 +8,16 @@ sidebar_position: -59
 
 # eCalc v13.0
 
+## Changes in results?
+
+> ✔️ **YES**: As a consequence of the bug fixes below, some numbers in results may have minor changes.
+
 ## Features
 
 ## Bug Fixes
 
 - There was an issue with returning the correct speed for the common shaft in a multiple streams and pressure train with interstage pressure when the interstage pressure could not be reached (invalid points). This has been fixed.
+- When aggregating rates we want invalid points to be treated as zero. In this case, aggregation of emissions resulted sometimes in 0, if at least one contributor had invalid results. This will now be correct. As a consequence of this, other places where we have invalid points, will now have results different from 0, such as power.  To emphasize, accepting models with invalid points in eCalc is ALWAYS frowned upon, as we cannot guarantee correctness of those points.
 
 ## Breaking changes
 
@@ -24,4 +29,4 @@ data on-the-fly, to e.g. reflect deterioration over time. See migration guide fo
 
 ### CLI
 
-- `--csv` will no longer disable the csv file, `--no-csv` should be used instead.
+- `--csv` will no longer disable the csv file, `--no-csv` should be used instead.