For Maplex line label placement, there is an option to change the label alignment but the alignment does not change afterwards.
Last Published: February 23, 2018ArcGIS for Desktop
Bug ID Number
BUG-000097603
Submitted
July 7, 2016
Last Modified
June 5, 2024
Applies to
ArcGIS for Desktop
Version found
10.3.1
Status
Known Limit
After review by the development team, it has been determined that this issue is related to a known limitation with the software that lies outside of Esri's control. The issue's Additional Information section may contain further explanation.
Additional Information
The Maplex label engine sets the alignment of the symbol, not the symbol dialog. See the stacking option to set these yourself.
In ArcGIS Pro we have disabled these symbol parameters while labeling.