Regarding the comment about needed a university degree to progress past wg cdr, I believe CAS joined straight from school so he has no first degree. His MA comes from staff college where it is available to all who want to do the extra work.
Beagle, you might have been the oldest flt cdr on promotion, but you would not have been the most senior - seniority comes from date of advancement not from age (cue Michael Caine and Stanley Baker’s exchange in Zulu!)