Sorry if I come back with the subject but is it consistent to have the English contingent of the medieval Navarrese ( 5816 ) being able to field both options so either PB with melee expert ( front rank ) OR separate men-at-arms and "common" PB as it is not the case in the Burgundian army but the English contingent is "almost" similar see : https://mortem-et-gloriam.co.uk/smf/index.php?topic=2741.0
It is also not clear that the small men-at-arms UG cannot be taken if you take melee expert PB
They are intentionally different. The list is how it is written. You can take the men at arms and the melee expert longbowmen.
Richard
Interesting