To exercise the privileges of a PPL you only need a Class 2 medical.
FCL.205.A PPL(A) — Privileges
(a) The privileges of the holder of a PPL(A) are to act without remuneration as PIC or co-pilot on
aeroplanes or TMGs engaged in non-commercial operations.
(b) Notwithstanding the paragraph above, the holder of a PPL(A) with instructor or examiner
privileges may receive remuneration for:
(1) the provision of flight instruction for the LAPL(A) or PPL(A);
(2) the conduct of skill tests and proficiency checks for these licences;
(3) the training, testing and checking for the ratings or certificates attached to this licence.