This is an excerpt from NPA 17b which clearly states that PPL FIs can be paid for teaching to PPL level. Of course, the jury is still out on this.
SECTION 2
Specific requirements for the PPL aeroplanes PPL(A)
FCL.205.A PPL(A) Privileges
(a) The privileges of the holder of a PPL(A) are to act without remuneration as pilotincommand or copilot of aeroplanes engaged in noncommercial
operations.
(b) Notwithstanding the paragraph above, the holder of a PPL(A) may receive remuneration for the provision of flight instruction for the LPL(A) or the PPL(A).