SelectMany with TPH and OfType throws System.ArgumentException

EfCoreBugSelectMany.cs

using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Diagnostics;
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Linq.Expressions;
using System.Threading.Tasks;

namespace EfCoreBugSelectMany
{
    class Program
    {
        static async Task Main(string[] args)
        {
            using (var context = new ClientContext())
            {
                //context.Database.EnsureDeleted();
                context.Database.EnsureCreated();

                // this query works
                var carsFromOffers = await context.Offers
                    .OfType<CarOffer>()
                    .Where(o => o.CompanyId == 1)
                    .Select(o => o.Car)
                    .ToListAsync();

                // this throws an exception
                // Property 'Car Car' is not defined for type 'EfCoreBugSelectMany.Program+Offer'
                var carsFromCompanies = await context.Companies
                    .Where(c => c.Id == 1)
                    .SelectMany(c => c.Offers.OfType<CarOffer>().Select(o => o.Car))
                    .ToListAsync();
            }
        }

        public class Company
        {
            public int Id { get; set; }

            // Navigation properties
            public ICollection<Offer> Offers { get; set; }
        }

        public abstract class Offer
        {
            public int Id { get; set; }

            [Required]
            public Company Company { get; set; }
            public int CompanyId { get; set; }
        }

        public class CarOffer : Offer
        {
            [Required]
            public Car Car { get; set; }
            public int CarId { get; set; }
        }

        public class BoatOffer : Offer
        {
            [Required]
            public Boat Boat { get; set; }
            public int BoatId { get; set; }
        }

        public class Car
        {
            public int Id { get; set; }
        }

        public class Boat
        {
            public int Id { get; set; }
        }

        class ClientContext : DbContext
        {
            protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
            {
                // TO USE SQL
                //optionsBuilder
                //    .UseSqlServer("Server=(localdb)\\mssqllocaldb;Database=EfCoreBugSelectMany;Trusted_Connection=True;MultipleActiveResultSets=true;Connect Timeout=30")
                //    .ConfigureWarnings(warnings => warnings.Throw(RelationalEventId.QueryClientEvaluationWarning));
                // TO USE INMEMORY
                optionsBuilder
                    .UseInMemoryDatabase(Guid.NewGuid().ToString())
                    .ConfigureWarnings(warnings => warnings.Throw(RelationalEventId.QueryClientEvaluationWarning));
            }

            protected override void OnModelCreating(ModelBuilder builder)
            {
                base.OnModelCreating(builder);

                builder.Entity<Company>().HasData(new Company
                {
                    Id = 1
                });
                builder.Entity<Car>().HasData(new Car
                {
                    Id = 1
                });
                builder.Entity<CarOffer>().HasData(new CarOffer
                {
                    Id = 1,
                    CompanyId = 1,
                    CarId = 1
                });
            }

            public DbSet<Company> Companies { get; set; }
            public DbSet<Offer> Offers { get; set; }
            public DbSet<CarOffer> CarOffers { get; set; }
            public DbSet<BoatOffer> BoatOffers { get; set; }
        }
    }
}

Project.csproj

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>netcoreapp2.1</TargetFramework>
    <LangVersion>latest</LangVersion>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.EntityFrameworkCore" Version="2.1.3" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.InMemory" Version="2.1.3" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="2.1.3" />
  </ItemGroup>

</Project>