Originally Posted by
javabytes
+1
My traveling companions have not gotten booted out of preferred seating after splitting the PNR. If their seat changes, though, you might not be able to get them back into Economy Comfort.
This is true for preferred seating, since the system doesn't do any sweeps looking for ineligible passengers. For EC, I have found that it re-checks eligibility during any changes to the itinerary (i.e. changed FF number) and during check-in.
When I've gone in and replaced my DL PM # with my Flying Blue Gold #, it instantly kicks me out and offers the 50% discount.