Whenever an RN warship visits a UK port, there are very often ship visits arranged for local schools and potential recruits in liaison with the nearest AFCO.
It's appreciated these visits are often a bit of a chore for an already busy operational warship but they really are invaluable. One thing that has really impressed me in recent years is the excellent quality of the Ships Company detailed as tour guides.
There was a time when you could expect a surly, disaffected AB who unwittingly ensured his draft would be extended due to the amount of people no longer wishing to join. I've been hugely impressed by the individuals (often YO's or ABs) who I've had the pleasure of meeting - a significant & noticeable change for the better.
With regard ships being visited whilst in refit, far from ideal for all concerned however it gives a realistic & balanced view, reflecting the fact that the job is not one long pleasure cruise. (Unless you are a woo).