Deniz Kılınç / İstanbul, May 4 (DHA) – Moody’s Investor’s Service has upgraded Residential Mortgage Securities 28 Plc’s three notes.According to Moody’s the upgrades are related to the recent increase in credit enchancement for the affected notes. Also Moody’s confirmed the ratings of the remaining tranches which had ‘sufficient credit enchancement’ to maintain their current ratings.