Identity columns get its value after the entity is saved.
Given the following table:
CREATE TABLE T2 ( ID INTEGER PRIMARY KEY AUTOINCREMENT, Value TEXT)
The following code shows you the id for the inserted row:
using (TestEntities entities = new TestEntities())
{
T2 t2 = new T2();
t2.Value = "some value";
entities.AddToT2(t2);
entities.SaveChanges();
Console.WriteLine(t2.ID);
}