Among the sparse changes in codelists 35 is an addition to List 51, the “Product Relation Code”. There are 42 classifications on this list, defining relationships like “is remaindered as” and “is facsimile of”. The additions reference related products for students and teachers. The use case isn’t explained in the documentation.
ONIX deals with educational texts in several sections.
List 21, the “Edition Type Code” includes identifications such as:
SCH – School edition – An edition intended specifically for use in schools
STU – Student edition – Where a text is available in both student and teacher’s
TCH – Teacher’s edition – Where a text is available in both student and teacher’s
editions; use also for instructor’s or leader’s editions
List 154 specifies “Content audience” including separate categories for “Teachers” and “Students”.
I could imagine a challenge in aligning each of these codes, and avoiding contradiction.
As for the future, there is an interesting announcement included with the release: Issue 36 of the codelists, planned for publication in January 2017, will be the last that is fully compatible with ONIX 2.1.