If you go to Admin --> Attributes and click the edit button on the tabs you mentioned you can see how many are available.
i.e. group string variables go up to 35. but group user variables only go up to 5.
Hope this helps.
I see 256 but I guess it is the attribute length limit. I am trying to see how many number of custom attributes can be created
If you look at the Database ID field in the attribute edit screen it says for example (CAS35) that means Attribute #35.
Here is a more detailed breakdown.
You can configure attributes for each of the following data types:
Note: The "ACL" data type is reserved only for the Access Control List fields (Other Business Owners, Other Technical Owners, Other Violation Managers) included with business source objects. It is not designed for use with extended attributes.
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