Newton, Mass.-based REIT Office Properties Income Trust (OPI) completed an exchange of an aggregate $20.99 million principal amount of its senior unsecured notes due 2026, 2027, and 2031, for $14.44 million of new 8% senior priority guaranteed unsecured notes due 2030. We view this transaction as distressed and tantamount to a default given that creditors received less than the full value they were originally promised. As a result, we lowered our issuer credit rating on OPI to 'SD' (selective default) and our issue-level ratings on its senior unsecured notes due 2026, 2027 and 2031, to ?D?. Our issue-level ratings on other obligations are unchanged. The downgrade follows OPI?s completion of its private debt exchange. In aggregate, the company exchanged $20.99