New legislation (from 22 July 2011) which grants under 18s the right to leave after a 'cooling off' period. Prior to this, discharge of 'unhappy minors' was at the discretion of the commanding officer.
This right is additional to an individual's Discharge As Of Right (DAOR) between the 2nd and 6th month of starting service.
Under 18s in all branches of the forces may now give 3 months' notice to leave (i.e. leave the regular service and join the Reserves) if they give notice in writing to their commanding officer any time before their 18th birthday. By mutual consent the 3 months' notice may be reduced.
The recruit can change their mind about leaving if they do so within the notice period and they can still give notice later on.
Additionally, the legislation also allows adults the possibility of having their 12 month notice period reduced by up to 6 months as long as it is done within one month of notice being given. This is at the discretion of the commanding officer.