diff --git a/ActiveCaptainSample/ActiveCaptainSample/ActiveCaptainAPIClient.swift b/ActiveCaptainSample/ActiveCaptainSample/ActiveCaptainAPIClient.swift
index 5dcc1a7..0548b14 100644
--- a/ActiveCaptainSample/ActiveCaptainSample/ActiveCaptainAPIClient.swift
+++ b/ActiveCaptainSample/ActiveCaptainSample/ActiveCaptainAPIClient.swift
@@ -91,10 +91,16 @@ class ActiveCaptainAPIClient {
         sendRequest(.post, components)
     }
 
-    func syncMarkers(tileX:Int, tileY:Int, lastModifiedAfter:String) -> Promise<String> {
+    func syncMarkers(tileX:Int, tileY:Int, lastModifiedAfter:String?) -> Promise<String> {
         var components = URLComponents(string:ActiveCaptainConfiguration.apiBaseURL)!
         components.path += "/api/v2/points-of-interest/sync"
-        components.queryItems = [URLQueryItem(name:"tileX", value:String(tileX)), URLQueryItem(name:"tileY", value:String(tileY)), URLQueryItem(name:"lastModifiedAfter", value:lastModifiedAfter)]
+        var queryItems = [URLQueryItem(name:"tileX", value:String(tileX)), URLQueryItem(name:"tileY", value:String(tileY))]
+
+        if let lastModifiedAfter = lastModifiedAfter {
+            queryItems.append(URLQueryItem(name:"lastModifiedAfter", value:lastModifiedAfter))
+        }
+
+        components.queryItems = queryItems
 
         return firstly {
             sendRequest(.get, components)
@@ -103,10 +109,16 @@ class ActiveCaptainAPIClient {
         }
     }
 
-    func syncReviews(tileX:Int, tileY:Int, lastModifiedAfter:String) -> Promise<String> {
+    func syncReviews(tileX:Int, tileY:Int, lastModifiedAfter:String?) -> Promise<String> {
         var components = URLComponents(string:ActiveCaptainConfiguration.apiBaseURL)!
         components.path += "/api/v2/reviews/sync"
-        components.queryItems = [URLQueryItem(name:"tileX", value:String(tileX)), URLQueryItem(name:"tileY", value:String(tileY)), URLQueryItem(name:"lastModifiedAfter", value:lastModifiedAfter)]
+        var queryItems = [URLQueryItem(name:"tileX", value:String(tileX)), URLQueryItem(name:"tileY", value:String(tileY))]
+
+        if let lastModifiedAfter = lastModifiedAfter {
+            queryItems.append(URLQueryItem(name:"lastModifiedAfter", value:lastModifiedAfter))
+        }
+
+        components.queryItems = queryItems
 
         return firstly {
             sendRequest(.get, components)
diff --git a/ActiveCaptainSample/ActiveCaptainSample/ActiveCaptainManager.swift b/ActiveCaptainSample/ActiveCaptainSample/ActiveCaptainManager.swift
index 706193b..3b9b1c0 100644
--- a/ActiveCaptainSample/ActiveCaptainSample/ActiveCaptainManager.swift
+++ b/ActiveCaptainSample/ActiveCaptainSample/ActiveCaptainManager.swift
@@ -333,14 +333,10 @@ final class ActiveCaptainManager {
         var lastModifiedAfter = lastModifiedAfter
         if lastModifiedAfter == nil {
             lastModifiedAfter = database.getTileLastModified(withTileX: Int32(tileCoordinate.tileX), tileY: Int32(tileCoordinate.tileY))?.markerLastUpdate
-
-            if lastModifiedAfter == nil {
-                return Promise.value(SyncResult.fail)
-            }
         }
 
         return firstly {
-            ActiveCaptainAPIClient().syncMarkers(tileX: tileCoordinate.tileX, tileY: tileCoordinate.tileY, lastModifiedAfter: lastModifiedAfter!)
+            ActiveCaptainAPIClient().syncMarkers(tileX: tileCoordinate.tileX, tileY: tileCoordinate.tileY, lastModifiedAfter: lastModifiedAfter)
         }.then { (syncResponse: String) -> Promise<SyncResult> in
             let resultCount = Int(self.database.processSyncMarkersResponse(withJson: syncResponse, tileX: Int32(tileCoordinate.tileX), tileY: Int32(tileCoordinate.tileY)))
 
@@ -374,14 +370,10 @@ final class ActiveCaptainManager {
         var lastModifiedAfter = lastModifiedAfter
         if lastModifiedAfter == nil {
             lastModifiedAfter = database.getTileLastModified(withTileX: Int32(tileCoordinate.tileX), tileY: Int32(tileCoordinate.tileY))?.reviewLastUpdate
-
-            if lastModifiedAfter == nil {
-                return Promise.value(SyncResult.fail)
-            }
         }
 
         return firstly {
-            ActiveCaptainAPIClient().syncReviews(tileX: tileCoordinate.tileX, tileY: tileCoordinate.tileY, lastModifiedAfter: lastModifiedAfter!)
+            ActiveCaptainAPIClient().syncReviews(tileX: tileCoordinate.tileX, tileY: tileCoordinate.tileY, lastModifiedAfter: lastModifiedAfter)
         }.then { (syncResponse: String) -> Promise<SyncResult> in
             let resultCount = Int(self.database.processSyncReviewsResponse(withJson: syncResponse, tileX: Int32(tileCoordinate.tileX), tileY: Int32(tileCoordinate.tileY)))