Join Date: Apr 2009
Location: Bye Delta
Programs: AA EXP, UA Silver, HH Diamond, IHG Plat, Hyatt Plat, Marriott Titanium, Nat'l EE, Avis PC, Hertz PC
Posts: 16,637
KVS will not show you DL upgrade inventory. ExpertFlyer did until Delta shut that down.
The inventory bucket for first class mileage/instrument upgrades is RP internally, but R when accessed through a GDS.
Confusingly, First Class tickets book into R, but award and upgrade space are separate.
There is presently no way to find mileage/instrument upgrade inventory without having a GDS subscription (not cheap or for the faint of heart), or contacting DL.