Difference between Exceptions in Manage Supply Lines and Manage Supply Request Exceptions

This question is from the perspective of planned order releases from Supply Planning in Supply Orchestration

In Supply Orchestration we can view exceptions in two places and both are mutually exclusive:

1.Manage Supply Lines : Shows all records in addition to exceptions (you can search by exception date)

2.Manage Supply Request Exceptions(you can search by exception date)

What is the difference between the two. The second category above seems to be records that have not even made it to Supply Orchestration and the first category are records that made it to Supply Orchestration but could not be processed further to create supplies . Is this understanding correct?