Ok will release a lot of unwanted youth before next time round and seeDo you have a lot of players in your youth team? I don't know if this has an impact for sure but i noticed that if i have a lot of youth players i seem to get a smaller intake in comparison to a smaller youth set up. I'm sure a more knowledgeable member of the forums such as Raikan007 will give you a proper answer.
That won't affect anything, as the youth intake are trialists and have their own team! It must be a bug, someone else had this problem the other day too...
Oh and the English youth intake is the 13th march, but obviously you have still passed it. Try reloading a save just before the youth intake to see if it works!