Amanda Bynes -- VICTORIOUS In Alleged Bong-Throwing Case

7:15 AM -- Amanda was just granted the ACD -- as we told you she would be -- and her next progress report was set for June. So, 6 months of good behavior ... and she's good to go.

Amanda Bynes has effectively BEAT THE RAP in her criminal case ... where she stands accused of throwing a bong out of her NYC apartment window.

Cops had claimed they came to Amanda's unit after getting complaints from neighbors she was smoking weed. Cops say they smelled weed in her unit and before they could do anything she threw a bong out the window.

Amanda -- who said she threw a flower vase and not a bong -- was charged with marijuana possession, evidence tampering and reckless endangerment.

Law enforcement sources tell TMZ ... the case will be resolved tomorrow in court. Here's what will happen. The case will be put on ice. Amanda will NOT enter a plea. If she keeps her nose clean and continues her therapy for the next 6 months, the charges will be formally DISMISSED and the case will be sealed. The fancy legal term -- Adjournment in Contemplation of Dismissal.

One reason the case is essentially being dropped ... cops didn't retrieve the glass for days, which means there's no proof what they eventually found was thrown by Amanda. Our TMZ producer spotted the broken glass first, which looked like a bong, but the evidence was contaminated by weather, time and cigarette butts.

We contacted Amanda's lawyer, Gerald Shargel, but he had no comment.