Reached out again last night and got a array of replies from delta..
Started with the cabin is full which is why you cant upgrade (....not true). Then the one interesting one after they escalated was a guy who told me that my ticket was purchased through a 3rd party (named my former companies travel app). I left that company a couple months ago, and had to cancel a trip which i got refunded directly as a e-credit, I applied that ecredit (plus a gift card, and cash) to pay for this booking. He first said my ticket was ineligible for upgrades because of the booking via the third party was 'rebooked' to this ticket (do restrictions travel with an ecredit?)....then said it had been transferred to delta so there wouldn't be any restrictions. When I pointed out I clearly was restricted he transferred me to yet another agent. That 3rd....4th? Agent also couldn't figure out exactly what was wrong, but managed to come up with a price for upgrades and recommended i basically do dummy bookings every few days and try to tell if PS/D1 has gotten 'cheaper' and then reach out for someone to quote me a change again.