ASSOCIATED LEVEL OF A PLAN VIEW

All plan views have an Associated Level.

This is the level that elements added in the view will be placed on by default, and the level the view's cut plane is based on.

Note that the parameter is grayed out - it can not be edited.

Associated Level can only be set when the view is created.

If you create a view by Duplicating the new view will have the same Associated Level as the duplicated view.

But if you create a new View via the Ribbon:

You an select for which level you want to create the View:

So always be aware of what Level you want a new view to be based on, and use the appropriate method to ensure you get what you expect.