Answer
If the Fed is credible in its plan to cut inflation, then the inflation level should fall quickly to the Fed's planned inflation level.
Work Step by Step
However, if the Fed's plan is not credible to cut inflation, then the inflation level could stay above the Fed's desired inflation level for some time. This could force the Fed to take extraordinary measures to cut inflation to the Fed's desired level. These extraordinary measures could be (but are not included to) selling more bonds than expected or buying fewer bonds than normal.
