Something I found interesting were the remarks about people moving on.
On average (if it can be as basic as that), what percentage of the crew are changed for each sailing?
I appreciate sailings may be months apart so they have to do something in between... but that must mean that fresh learning curve is present at the start of every voyage and is it the same for all vessels?.
I think it was ever thus. Every military unit has a constant turnover of people for many reasons.