Quite right, S a S!
Incidentally, a Class 1 medical is not compulsory for instructing; it is possible for PPL holders to conduct non-remunerated PPL instruction (although they still have to learn all about the Inter Tropical Convergence Zone and know how wide the red stripes need to be on the streamers below tethered kites....
).
Young eager puppy FIs building their hours pre-airline application do indeed need supervising
very carefully!