Flagstar Bank is set to issue its third jumbo mortgage-backed security in as many quarters, according to presale reports published this week. The bank plans to issue a $487.66 million deal, which follows a $576.44 million deal from October and a $443.79 million issuance in July. Underwriting characteristics across the three MBS are largely similar. The new issuance includes mortgages with an average credit score of 761, an average combined loan-to-value ratio of 67.4 percent and ...