adderall xr 10 mgs | ADHD Information

So here is my question, im currantly taking Adderall xr 10 milligrams daily for my adhd, im prescribed adderall and have really bad adhd. my question is im going to start taking a new dosage as of tuesday may31st per my doctors request, and monday may 23rd was my last day on the xr 10 milligrams. I want to drink beer Friday may 27th and i want to also drink some whiskey may 29th sunday. and wanted to know when will the adderall xr  will completly be out of my system if monday  may23rd was my last day taking the 10 milligrams. like what is the half life and all. plese respond.thank you all.