WRT DocID 1507116.1 is there a way to revert the lob retention to "default"

DocID 1507116.1 has the DBA reviewing:

select max(MAXQUERYLEN) from V$UNDOSTAT;

select to_number (VALUE) from V$PARAMETER2 where NAME='undo_retention';

To ensure that the instance is configured to maintain the worst-case undo for one's current needs.

However, it has us go on to see what lobs have a "custom" unto retention that's below these values. I notice many lobs don't have this column set and one presumes this means "default" and so it "inherits" the undo retention from the instance.

My question is, if the preceding statement is correct, is there a way to remove these lob retention "customizations" so it revert's to the instance's?