What date should be used for an Approved but not accepted application?

1 - the date the application was approved by the bank?
2 - the date the customer said he wasn't interested in pursuing the application - evidenced with email?

#2. That's when the final 'action' was taken on the file.

At another bank I worked at, we used formal commitment letters that contained an expiration date. We used that date to kill the loan unless the customer indicated so at an earlier date. Some of these just linger around forever, and having the expiration date gave us a bright line for that purpose.

From the Getting It Right:
5 Action taken date—approved but not accepted. For a loan approved by an institution but not accepted by the applicant, the institution reports any reasonable date, such as the approval date, the deadline for accepting the offer, or the date the file was closed. Although an institution need not choose the same approach for its entire HMDA sub mission, it should be generally consistent (such as by routinely using one approach within a particular division of the institution or for a category of loans).