Finally received a reply from customer care a week later. Not sure if this is even worth responding too…

Hello Alexander,

RE: Case Number XXXXXXXX

Thanks for writing about the service you and your mother received on your recent trip. I know how you felt when you were unable to use your Systemwide Upgrade Certificates for an upgrade as planned. Please be advised that inventory for advance upgrade is limited. Although there are open seats, those seats are available for purchase only and not available for complimentary upgrades. When advance upgrade inventory is no longer available but First Class seats are available, our Medallions will be added to the airport upgrade standby list and will only be cleared at time of departure. Again, I’m sorry we were unable to accommodate your upgrade. We offer Systemwide Upgrade Certificates as a Delta Choice benefit and we suggest you visit our website for a list Terms and Conditions.

We Hear You
I’ve passed your comments directly to the Airport Customer Service and SkyMiles Marketing leadership teams, so they can consider your experience when making needed changes to improve our service.

Bonus Miles
As a goodwill gesture, I’m adding 7,500 bonus miles to your SkyMiles account. They should be transferred into your account within three business days.

We love that you’re a Platinum Medallion member. We hope your next trip is pleasant in every way.

Regards,

XXXXXXXXXX
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