Five hours later, the 26-year-old from Oyster Bay in Sydney's south, was dead.

Now the close high school friend who supplied her with a "yellow Snapchat" ecstasy pill and an MDMA capsule has been sentenced to a minimum of six months in jail.

Physiotherapist Daniel Dung Huynh, 26, stared straight ahead after magistrate Michelle Goodwin read out the one-year maximum sentence at Burwood Local Court on Monday.

A number of family members and supporters wept.

Shortly after Huynh was taken into custody by Corrective Service officers, his legal team applied for him to be released on bail, pending an appeal against his sentence.

Ms Goodwin allowed Huynh to be released on bail on the condition that he surrender his passport and report to police three times a week.

"Unfortunately these offences are prevalent in our community," Ms Goodwin said.

"The language in those conversations indicate to me that he is an organised and experienced person in the supply of the drugs. Supply is supply," she said.

Huynh previously pleaded guilty to two counts of supplying a prohibited drug and has been free on bail.

During a sentencing hearing, Carolyn Davenport, SC, argued that her client should not be sentenced for the death of Ms Choi, but for the supply charges.

She said he was not a drug dealer but a person who had organised some drugs for his friends.

"As tragic as her death was, he is to be sentenced on the fact that he supplied her with a small amount of drugs," she said.

"There is no doubt that, as a result of his actions on that day, he will pay a penalty for the rest of his life."

Police facts previously tendered in court outlined how Huynh and Ms Choi were part of a group conversation called "Bulk4Stereonickkk" on the WhatsApp messaging application in the lead-up to the music festival last November.

In this group chat Huynh, Ms Choi, her boyfriend Sam Song and eight other friends discussed "lolly numbers" as well as other festival plans.

The police facts state Ms Choi and Mr Song each transferred $120 to Huynh to buy, for each of them, one clear capsule of MDMA and one yellow tablet, also containing MDMA, imprinted with the logo of another messaging app, Snapchat.

They're called yellow snapchats," Huynh said on WhatsApp about the ecstasy pills.

"About 200-250mg in concentration. Its suggested all over the net to take half. Then the other half and hr later. Btw if ever caught and brought into questioning by cops and u don't have anything on you Deny deny deny and say it must have been the weird mirky water you drank from a random."

Ms Choi responded by saying: "Hmm have a bad track record with halves lol."

Huynh: "At most then syl do half and then the next half 15 mins later."

Ms Choi: "Yea I suppose".

After Ms Choi's death, her boyfriend told police that she had said to him at the festival, "I took it" at 5.15pm on November 28.

Mr Song also said he saw Ms Choi swigging from a water bottle, which she said had "stuff in it".

Ms Choi was later taken to Concord Hospital where she was pronounced dead about 10.20pm.

In October, a coronial inquest will examine what caused her death.