Forgot to synthesize @property

plugin.xml

@@ -3,7 +3,7 @@
 <plugin xmlns="http://www.phonegap.com/ns/plugins/1.0"
     xmlns:android="http://schemas.android.com/apk/res/android"
     id="org.transistorsoft.cordova.background-geolocation"
-    version="0.3.1">
+    version="0.3.2">
     <name>CDVBackgroundGeoLocation</name>
     <description>Cordova Background GeoLocation Plugin</description>
     <license>MIT</license>

src/ios/CDVBackgroundGeoLocation.m

@@ -48,6 +48,7 @@
     NSInteger desiredAccuracy;
     CLActivityType activityType;
 }
+@synthesize syncCallbackId;
 
 - (void)pluginInitialize
 {