Ryan Bennett-Morris was allowed to spend Christmas with his family after pleading guilty to drugs charges in December, but has now been sentenced.
The Croydon man was just 18 when he was caught in Worthing with Class A drugs in October last year.
Appearing in court last month, Bennett-Morris pleaded guilty to: possessing heroin with intent to supply, possessing crack cocaine with intent to supply, possessing cannabis and possessing criminal property.
Judge Shani Barnes told him: “You are in big trouble and I am not making any promises, but I will adjourn to give you time to think about your mitigation and prepare for your future.
“This is a really serious criminal offence.
“Spend Christmas with your family and make plans.”
The case was adjourned for pre-sentence reports.
Bennett-Morris appeared at Brighton Crown Court again on Friday for sentencing.
He was sentenced to two years and four months in a young offenders' institution.
An order was made for destruction of the drugs and forfeiture of £664 in cash.
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