Best practices for troubleshooting incremental ELM IB async errors

For the most part our incremental async messages from PeopleSoft HCM to ELM are working fine but we have a small number of errors cropping up and I'm wondering about best practices for troubleshooting these.

In this particular case, there are two rows for the same learner. Row two above is a 'Correction' row (audit_actn = 'C'), though I don't really see a change from the row that already exists. Row one is an add row (audit_actn = 'A') and it appears that the learner was moved from one department to another.

Only theory I have is that the new department has the same effective date as row 1. Perhaps the new department and learner department change got picked up in the same async process. And even though the department is there now, perhaps it wasn't there when the async process first ran? This doesn't completely make sense to me though because this sort of change can happen and unless the async process is running in a particular order, it's not like I can control the order of data load from the run control page.