What is Seller type?

Seller type is how a brand describes itself: a network that owns and runs its own mobile network, or an MVNO that resells service on someone else's network. The distinction tells you who controls the radio side of your line and who sets the price, so it shapes coverage, network features and the deals on offer. 019 Mobile is listed as mvno and 1pMobile as mvno, while 1&1, 2degrees and 3 Denmark each list network, network and network.