NEW YORK–(BUSINESS WIRE)–Kroll Bond Rating Agency (KBRA) assigns preliminary ratings to 27 classes of mortgage pass-through certificates from Flagstar Mortgage Trust 2018-1 (FSMT 2018-1), a prime RMBS transaction with both non-agency jumbo (63.5%) and high-balance conforming (36.5%) mortgage loans. The FSMT 2018-1 pool comprises 754 first-lien, prime residential mortgage loans with an aggregate principal balance of $487,656,132 as of the cut-off date. The collateral consists entirely of fully