Class ratings within a NPPL(A) are mutually exclusive in terms of privileges. Therefore, the holder of a NPPL(A) with a SSEA class rating may not act as PIC of a microlight without a microlight class rating. See ANO Schedule 7 Part B Section 2:
Subject to paragraph (2) and to the conditions of the licence in which it is included, a SSEA class rating entitles the holder to act as pilot in command of any SSEA with a maximum take off weight authorised of not more than 2000kg excluding any such aeroplane which is a SLMG or a microlight aeroplane.
In order to act as PIC on microlights, the holder must complete training and test in accordance with the NPPL document quoted above, which is reproduced in CAP 804 Section 5 Part A Appendix 1.
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