That was kind of my point, I can't reconcile what is appropriately qualified either. My assumption was for example a CRI who meets the 30hrs on type or who holds a microlight licence would be appropriately qualified to provide differences training?
Privileges
Details of licence privileges can be found in Schedule 8
of the Air Navigation Order, (please also refer to
Section A, Appendix F).
The holder of a UK JAR-FCL licence with SEP rating
may also subject to completion of differences training
with an appropriately qualified flying instructor, exercise
the privileges of their licence on microlight aeroplanes
and SLMG’s in UK airspace only, without the necessity
of obtaining a NPPL (the normal licence for such
aeroplanes). However, any experience gained in
microlight aeroplanes or SLMG’s cannot be counted
towards the flying experience necessary to revalidate
the SEP rating.