ok. I've been looking over the FA 997 that our one client has been sending.
I noticed that when they are sending a 997 for a PR (855), they only
use AK1 and AK9, but when they send a 997 for a IN (810), they also
include the AK2 and AK5.
As far as I can figure, one would omit the AK2/AK5 if...