On today's DL10 flight? That's not what I see. For D1 I see -- J5 C5 D5 I5 Z5 . Dummy booking is not particularly useful since lower fares will not be available for purchase this close in. From what I've seen, FCM offer is generally based on availability in the lower buckets and price does not have relationship with your original fare or booking class. Could be un-checking you in was not sufficient to return the offer.

Upgrades will not be available on delta.com or the Fly Delta app if:

• Any flight segment of your trip is departing the United Kingdom, France, India, Ghana or Honduras
• You have already checked in to your flight
• Any segment of your flight is operated by a partner airline