Queries involving DATETIME behave differently between SQL Server versions 2013 & 2016

EfConcurrencyTests.cs

using System;
using System.Configuration;
using System.Data.Entity.Infrastructure;
using System.Data.SqlClient;
using System.Linq;
using NUnit.Framework;

namespace DbEfConcurrencyTests
{
  [TestFixture]
  public class EfConcurrencyTests
  {
    [TestCase("sqlserver2013", 0)]
    [TestCase("sqlserver2013", 1)]
    [TestCase("sqlserver2013", 2)]
    [TestCase("sqlserver2013", 3)]
    [TestCase("sqlserver2013", 4)]
    [TestCase("sqlserver2013", 5)]
    [TestCase("sqlserver2013", 6)]
    [TestCase("sqlserver2013", 7)]
    [TestCase("sqlserver2013", 8)]
    [TestCase("sqlserver2013", 9)]
    [TestCase("sqlserver2016", 0)]
    [TestCase("sqlserver2016", 1)]
    [TestCase("sqlserver2016", 2)]
    [TestCase("sqlserver2016", 3)]
    [TestCase("sqlserver2016", 4)]
    [TestCase("sqlserver2016", 5)]
    [TestCase("sqlserver2016", 6)]
    [TestCase("sqlserver2016", 7)]
    [TestCase("sqlserver2016", 8)]
    [TestCase("sqlserver2016", 9)]
    public void Can_update_a_record_whose_concurrency_field_has_been_modified_in_the_non_disconnected_state(string connectionName, int endTickDigit)
    {
      var expectedId = Guid.NewGuid().ToString();
      var ticks = DateTime.Now.Ticks;
      var creationTime = new DateTime(ticks - (ticks % 100000) + endTickDigit * 10000);
      var sampleObject = new SampleObject
      {
        Id = expectedId,
        ModifiedAt = creationTime
      };
      Console.WriteLine($"Sample, before DB storage: ModifiedAt.Ticks={sampleObject.ModifiedAt?.Ticks}, Id = {sampleObject.Id}");

      WriteObject(connectionName, sampleObject);

      var expectedModifiedAt = DateTime.Now.AddSeconds(1);
      var connectionString = GetConnectionString(connectionName);
      using (var connection = new SqlConnection(connectionString))
      using (var context = new TestingContext<SampleObject>(connection))
      {
        var sample1 = context.Values.Find(expectedId);
        Console.WriteLine($"Sample1, after DB retrieval: ModifiedAt.Ticks={sample1.ModifiedAt?.Ticks}, Id = {sample1.Id}");
        sample1.ModifiedAt = expectedModifiedAt;
        Console.WriteLine($"Sample1, after modification: ModifiedAt.Ticks={sample1.ModifiedAt?.Ticks}, Id = {sample1.Id}");

        using (var innerContext = new TestingContext<SampleObject>(connection))
        {
          var sample2 = innerContext.Values.Find(expectedId);
          Console.WriteLine($"Sample2, after DB retrieval: ModifiedAt.Ticks={sample2.ModifiedAt?.Ticks}, Id = {sample2.Id}");
          sample2.ModifiedAt = DateTime.Now.AddSeconds(14);
          Console.WriteLine($"Sample2, after modification: ModifiedAt.Ticks={sample2.ModifiedAt?.Ticks}, Id = {sample2.Id}");
          innerContext.SaveChanges();
          Console.WriteLine("Sample2 saved to DB");
        }
        Console.WriteLine("Sample1 about to saved to DB");
        Assert.That(
          () => context.SaveChanges(),
          Throws.Exception.TypeOf<DbUpdateConcurrencyException>());
      }
    }

    [TestCase("sqlserver2013", 0)]
    [TestCase("sqlserver2013", 1)]
    [TestCase("sqlserver2013", 2)]
    [TestCase("sqlserver2013", 3)]
    [TestCase("sqlserver2013", 4)]
    [TestCase("sqlserver2013", 5)]
    [TestCase("sqlserver2013", 6)]
    [TestCase("sqlserver2013", 7)]
    [TestCase("sqlserver2013", 8)]
    [TestCase("sqlserver2013", 9)]
    [TestCase("sqlserver2016", 0)]
    [TestCase("sqlserver2016", 1)]
    [TestCase("sqlserver2016", 2)]
    [TestCase("sqlserver2016", 3)]
    [TestCase("sqlserver2016", 4)]
    [TestCase("sqlserver2016", 5)]
    [TestCase("sqlserver2016", 6)]
    [TestCase("sqlserver2016", 7)]
    [TestCase("sqlserver2016", 8)]
    [TestCase("sqlserver2016", 9)]
    public void Can_return_a_record_based_on_a_DateTime_field(string connectionName, int endTickDigit)
    {
      var expectedId = Guid.NewGuid().ToString();
      var ticks = DateTime.Now.Ticks;
      var creationTime = new DateTime(ticks - (ticks % 100000) + endTickDigit * 10000);
      var sampleObject = new SampleObject
      {
        Id = expectedId,
        ModifiedAt = creationTime
      };

      WriteObject(connectionName, sampleObject);

      SampleObject sample1;
      var connectionString = GetConnectionString(connectionName);
      using (var connection = new SqlConnection(connectionString))
      using (var context = new TestingContext<SampleObject>(connection))
      {
        sample1 = context.Values.First(x => x.ModifiedAt == creationTime);
        Assert.That(sample1, Is.Not.Null);
      }
    }

    private static void WriteObject(string connectionName, SampleObject sampleObject)
    {
      var connectionString = GetConnectionString(connectionName);
      using (var connection = new SqlConnection(connectionString))
      using (var context = new TestingContext<SampleObject>(connection))
      {
        context.Values.Add(sampleObject);
        context.SaveChanges();
      }
    }

    private static string GetConnectionString(string connectionName)
    {
      return ConfigurationManager.ConnectionStrings[connectionName].ConnectionString;
    }
  }
  
  public class SampleObject
  {
    public string Id { get; set; }

    [ConcurrencyCheck]
    [Column(TypeName="datetime")]
    public DateTime? ModifiedAt { get; set; }
  }
  
  public class TestingContext<T> : DbContext where T: class
  {
    public DbSet<T> Values { get; set; }

    public TestingContext(DbConnection connection) : base(connection, false)
    {
      Database.Log = Console.WriteLine;
      Database.SetInitializer<TestingContext<T>>(null);
    }

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
      modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
      modelBuilder.Properties<DateTime>().Configure(p => p.HasColumnType("datetime"));
    }
  }
}

// Nuget package dependencies: NUnit-3.7.1, EntityFramework-6.1.3

/* 
// App.Config content:
  <connectionStrings>
    <clear />
    <!--
    this should point to a SQL Server 2013 DB (though it's my understanding the behavior on a SQL Server 2014
    server is equivalent)
    -->
    <add name="sqlserver2013" providerName="System.Data.ProviderName" connectionString="...;Data Source=MySqlServer2013" />
    <!-- this should point to a SQL Server 2016 DB -->
    <add name="sqlserver2016" providerName="System.Data.ProviderName" connectionString="...;Data Source=MySqlServer2016" />
  </connectionStrings>
// */

/*
// SQL Server Schema
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE TABLE [dbo].[SampleObject](
	[Id] [varchar](50) NOT NULL,
	[ModifiedAt] [datetime] NULL,
 CONSTRAINT [PK_SampleObject] PRIMARY KEY CLUSTERED 
(
	[Id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]

GO
// */