It's the passenger variant for the 787-8 that's all. There's a freighter variant as well, 787-8F it all depends how the airline decides to put it into their system. For example, KLM uses 74M for their 747-400 Passenger/Cargo a/c whereas another airline might put 744 Combi for the same a/c. If this KLM flight was also a Delta code share, DL may show it as a 744 Combi.

It's the same in your case here 787-8 pax, 787-8 Jet, 787-8F, etc.

On you itinerary, it shows as one leg the a/c being 787-8 pax and then another leg being 787-8 Jet? Are any of these flights code shares?