Just as not all ITV regions have an HD output, the same applies to the +1 channels. It costs money to install loop systems for every region, so in the ones that don't ITV supply the nearest one available.
Whether you have Virgin, Satellite or Freeview, the channel choice will be the same.
Cable customer since 1993. Services: FH TV, Sky Sports & Movies (2xV6), Talk Anytime Phone, VIVID 350, Virgin PAYG Mobile