In the earlier bits, if you changed an association to an inhertiance, the type that becamse the derived type lost its mappings and th emappings for any associations.
Depending on how complex that type is, recreating all of that could be challenging.
I just tried this out in the new bits and the mappings and association mappings all remain intact.
This is great and it will save a tree too, since I can go remove all of that explanation about how to deal with that problem from Chapter 5 of my book!
Sign up for my newsletter so you don't miss my conference & Pluralsight course announcements!