I don't believe that they have had cadets for a couple of years now, atleast they were all gone when I finished up.
As for why arent they upgrading, Is that an assumption made from their advertisment, just because they are advertising for Captains doesnt mean that they arent upgrading........ unless I am wrong.
It also does not mean that they will only hire captains with time on type, it's becoming a drying field again and I think quite quickly