I have ASP.NET Core application that tracks work crews. `WorkCrewMembers` is the class that contains crew members. It has a key into `WorkCrew` class that has a somewhat clumsy list of `TimeSpan?` fields specifying when this crew starts working on specific days of the week: `SunStart, MonStart, TueStart, WedStart, ThuStart, FriStart, SatStart`. The classes are generated from legacy database. I have the following code that was working happily in ASP.NET Core 1.0.1

```
public class Program
{
    public static void Main(string[] args)
    {
        using (DBContext context = new DBContext()) {
            var lstWorkCrew = (from m in context.WorkCrewMembers
                where m.WorkCrew.TodayStartTime() != null
                select m.WorkCrewId).ToList();
            Console.WriteLine($"Today {lstWorkCrew.Count} work crews");
        }
    }
}

public partial class WorkCrew {
    public TimeSpan? TodayStartTime() {
        TimeSpan?[] starts = {
            SunStart, MonStart, TueStart, WedStart, ThuStart, FriStart, SatStart
        };
        int dayOfWeek = (int)DateTime.Now.DayOfWeek;
        return starts[dayOfWeek];
    }
}

```

However, when I upgraded the packages to [1.1](https://blogs.msdn.microsoft.com/webdev/2016/10/25/announcing-asp-net-core-1-1-preview-1/), I am getting the following error in the line with `m.WorkCrew.TodayStartTime()`:

> 
> Unhandled Exception: System.ArgumentException: Method 'System.Nullable`1[System.TimeSpan] TodayStartTime()' declared on type 'WorkCrew' cannot be called with instance of type 'System.Int32'
> 
> 
> 

Interesting that if I do `from w in context.WorkCrew where w.TodayStartTime() != null select w` it works fine.

Is it a breaking change in 1.1? Or it is something that should throw an exception earlier because my code is not legit? Or simply a bug that Microsoft will fix?