No Id on category when creating it from BO

No Id on category when creating it from BO.
If i create a category from BO and then look at history i see this “Property ‘Id’ was removed.”
We have code created categories in our solution, but the customer added a new category manually which caused alot of “currentCategory.Id” to give null.
And it’s not possible to set an Id from BO.
Is that by design? It would be usefull to be able to set Id on categories that is manually created

Litium version: 5 and 6

Yes, the Id is null by design, since it is used for integration purpose.