Use the UpdateBlockAttributes command to update all instances of Blocks with new or modified BlockAttributes.
You can change or add BlockAttributes to an existing Block definition by redefining the Block with the MakeBlock command.
Another way to modify the definition and properties of BlockAttributes is with the EditComponent command.
Both commands update the geometry of all instances of the redefined Block, but they do not automatically update the BlockAttributes that have been modified.
To update BlockAttributes:
If you specified a Block, all BlockAttributes in the drawing are rebuilt.
Access
Command: UpdateBlockAttributes