Pippa wrote: Presumably if I fail to stay in the support group after my next assessment and end up in the WRAG, I will (after one further year on CB ESA) be transferred to Universal Credit and not New ESA though?
No you would not have to claim UC.
ESA is a single benefit with payments based on the claimants Contribution history or their earnings, so any ESA(IR) you would be entitled to would be paid as part of your existing claim and there is no need for a new claim, the trigger for UC.
If you think that you would be entitled to ESA(IR) if moved to the WRAG (after 365 days), then you may be entitled to ESA(IR) payments now! It might be worth your checking your eligibility on one of the benefit calculators.
www.gov.uk/benefits-calculators Gordon