@Gailquinn
Sky Mobile is an MVNO on the O2 network, which means it is physically carried over O2 masts and associated technical infrastructure (as are, for example, giffgaff and Tesco Mobile)
As @caesarome indicates, any company-specific features, including marketing promotions, are entirely separate.
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Sky Glass 55" (on ethernet) & two Stream Pucks (one ethernet / one WiFi)
BT Halo 3+ Ultrafast FTTP (500Mbs), BT Smart Hub 2
