I don't fully understand the UK IBM salary rages, so I will not comment on that. But anything below Band 7 will be an insult unless your experience is not relevant to what you will be doing at IBM. Generally, as a new grad, with good performance, you will be promoted at IBM after 2 years. (one year if exceptional - 3 years, if mediocre). Band 8 will be a stretch also as they will be hesitant to count your experience as that worthy (they tend to be a bit cheap, unless you have some sort of hot skill they want). So, to net it out, I would expect Band 7. My experience is in the non-tech consulting arm in North America though.