Our school gives "minimum target grades" (MTG) rather than predicted grade for GCSE. I'm not sure of the exact definition, but in practical terms it means that 8 is the maximum they would ever give as a minimum target, even though they know some of those with a MTG of 8 are fully capable of getting a 9 if they work consistently hard and have a good day.
DS has lots of MTGs of 8, and is highly likely to get several 9s, as he did in his mocks. He wants to apply to a super-selective sixth form that uses "predicted grade" as an entry criteria. I'm amazed they're allowed to use something so subjective, and I'm wondering what they will do in our case - will they just take the MTG as the predicted grade or are they likely to put the MTGs into context, e.g. by also looking at the Mock results?