What you should not expect is for the matter to be adjourned for it to be dealt with at the Crown Court (and your solicitor – if that’s what he calls himself) should be replaced by somebody who knows what he is talking about.
You will appear in the Youth Court where you will have the opportunity to enter your guilty plea. The Youth court will sentence you. A committal to the Crown Court for people under 18 is only available if the child or young person is:
a. convicted of an offence capable of being a grave crime on summary trial and it appears to the court that the offence is such that the Crown Court should have the power to sentence the child or young person to long-term detention, or
b. categorised as dangerous and the public needs protecting from future serious harm from a violent or sexual offender, a committal to the Crown Court for an extended sentence may be considered. This would need to be a sentence of at least four years imprisonment.
Option (a) is not applicable because Section 20 is not considered a “grave crime” for these purposes.
To invoke option (b) the court would have to be satisfied that you present a danger to the public and an extended sentence is necessary. With no record of violence there is no way they can come to this conclusion.
You will probably be given a “Referral Order”. Any decent solicitor will know that for this type of offence and without any previous record, the court will have virtually no other option. Your solicitor will tell you what this is (if he knows, that is, or can be bothered to look it up).