The insured long-term 'A' rating on the £192.65 million index-linked senior secured bonds (including £30 million of variation bonds) due 2043 issued by U.K.-based special purpose vehicle BY Chelmer PLC (ProjectCo) reflects the unconditional and irrevocable guarantee provided by Ambac Assurance U.K. Ltd. (local currency A/Negative/--) of payment of scheduled interest and principal on the bonds. The underlying 'BBB' rating on the debt reflects a combination of factors outlined below. ProjectCo is using the funds to finance the design, construction, and maintenance of new 600-bed health care facilities for Broomfield Hospital, in Chelmsford, Essex, for the Mid Essex Hospital Services National Health Service (NHS) Trust. The 35-year project agreement was signed on Dec. 6, 2007. The facilities comprise a five-story
