Colts/geldings in training

Maybe a slightly odd question, as its more a question for a trainer-however I'm sure some of you would be able to answer.

I know of a colt (yes its one of those colts) who even though he was a slightly backward 2 yo and didn't run, is still 'in training'.  He's still cantering, although not in full work, so kind of 'ticking over'.  Most of the geldings/fillies are (or have been) 'on holiday' before coming back in.

Is this just a routine sort of thing as he's a colt (I'm led to believe you don't turn colts out) or is the trainer maybe wanting to keep him going as he wants to get him out early (or maybe even on the AW)?

Or something else?