There are two reasons to convert a block to a group:
1) Individual objects in a group can be edited and modified while individual objects in a block cannot.
2) When editing a block, converting it to a group makes it easier to convert back to a block after it is edited.
When you convert a block to a group you are, in essence, adding a local copy of the block to the drawing. You can now modify the group as needed without affecting any objects that reference the original block.
Object Library
Block Files
Blocks
Inserting Blocks
Creating Blocks
Using Variables
Editing a Block Reference
Editing Blocks
Using Blocks from Other CAD Programs
Storing Blocks in the Drawing
Grouping Drawing Objects
No CAD Zone Drawings
Using Drawing View
Smart Drawing Objects
Working with Drawing Objects
Drawing Commands
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