An increase in interest rates by the Federal Reserve is likely to be accompanied by a change to a Fed program that could have a significant impact on investors’ cost to finance purchases of MBS, according to industry analysts. The Fed could increase interest rates as soon as Dec. 16. In a report released this week, analysts at Deutsche Bank Securities noted that Fed officials have discussed removing a cap on the Fed’s overnight reverse-repurchase program when interest rates increase. “That program will almost surely put...