Access to datetrack mode in table trigger

Two questions:

a) can I access the datetrack mode that was used to update a table within a trigger on that table?  For example, when the user adds the employment_category, it is always an update to the per_all_assignments_f table.  Is there a way to tell whether the user used UPDATE or CORRECTION mode?

b) I want to put a trigger on this table in order to cause an insert on a custom table.  Are there any negatives to this, any reasons why this shouldn't be done, or any better ways to do this?

We are using EBS 12.1.3.  Please let me know if you need add'l information.