Originally Posted by
KT550
(I couldn't edit my previous post).
Your Delta flights that were operated by a regional/franchise will be listed under the operating airline, not DL.
Here the flight number range for the DL Connection flights
flights 3283-4434 Pinnacle - 9E
Connection flights 4439-4858, 7362-7431 SkyWest airlines - OO
flights 4869-5632 expressjet airlines - EV
flights 5680-5859 Compass airlines - CP
flights 5868-6012, 7300-7331 Shuttle america - S5
flights 6030-6172 Chautauqua airlines - RP
flights 6184-6298 goJet airlines - G7