Minor:

Fix BukkitLegacyMappings method map usage
Move obtaining legacy block to default clause
Task should be async

Core/src/main/java/com/github/intellectualsites/plotsquared/plot/util/TaskManager.java

@@ -32,7 +32,7 @@ public abstract class TaskManager {
             if (IMP == null) {
                 throw new IllegalArgumentException("disabled");
             }
-            return IMP.taskRepeat(runnable, interval);
+            return IMP.taskRepeatAsync(runnable, interval);
         }
         return -1;
     }