仅当设备被锁定PIN码或无PIN码时，iOS位置更新才会收到50％的时间

Question

在屏幕锁定测试时，我在iOS应用中看到了一些意外行为。

流程是：

1）应用程序通过content-available标志

接收静默推送通知

2）App通过现有的CLLocationManager startUpdatingLocation调用

请求位置信息

3）收到位置更新后，将使用信息进行API调用

当应用在前台以及应用在后台时，流程会按预期工作。

如果我在收到推送通知时使用屏幕锁定按钮（启用或不启用PIN）锁定设备，则会调用startLocationUpdates方法，但仅在大约50％的时间内收到回调didUpdateLocations。

感谢有关此行为原因的任何信息。

基本代码流

-(void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler
{
    if(self.deviceLocationManager == nil)
    {
        NSLog(@"setUpLocation - Creating a LocationManager.");     
        self.deviceLocationManager                 = [[CLLocationManager alloc] init];
        self.deviceLocationManager.delegate        = self;
        self.deviceLocationManager.desiredAccuracy = kCLLocationAccuracyBestForNavigation;
        self.deviceLocationManager.distanceFilter  = kCLDistanceFilterNone;
        self.deviceLocationManager.pausesLocationUpdatesAutomatically = NO;

        if ([self.deviceLocationManager respondsToSelector:@selector(requestAlwaysAuthorization)])
        {
            [self.deviceLocationManager requestAlwaysAuthorization];
        }
        if ([self.deviceLocationManager respondsToSelector:@selector(setAllowsBackgroundLocationUpdates:)])
        {
            [self.deviceLocationManager setAllowsBackgroundLocationUpdates:YES];
        }
    }
    else
    {
        self.deviceLocationManager.desiredAccuracy = kCLLocationAccuracyBestForNavigation;
        self.deviceLocationManager.distanceFilter  = kCLDistanceFilterNone;
        self.deviceLocationManager.pausesLocationUpdatesAutomatically = NO;
    }
    [self.deviceLocationManager startUpdatingLocation];
    completionHandler(UIBackgroundFetchResultNewData);
}


-(void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
{
    NSLog(@":::: NEW LOCATION UPDATE RECEIVED ::::");
    CLLocation *location = [locations lastObject];
    CLLocationAccuracy horizontalAccuracy = location.horizontalAccuracy;
    NSLog(@"::::appDelegate - NEW LOCATION UPDATE ACCURACY IS - %f",horizontalAccuracy);
   //Make the API call here.......
}