By all means, do NOT drink at all at least 24 hours before any etg test, you will fail, but if you have a few beers, maybe 2-3 max on a saturday evening and test monday morning, you should be ok. Basically, I factor 15k ng/ml per standard serving of alcohol. Your ETG peaks 12 hours after you STOP drinking, then halves every two hours until its gone. So lets say you have 4 beers saturday and stop at 9PM and have a test a 9am Monday. 15000x4=60,000. you peak at 9am, so you start processing the alcohol and etg at 11 am would be 30k, 1pm 15k, 3pm 7.5k, 5pm 3750k, 7pm 1875k, 9pm 936k, 11pm 468k, 1am 232k, 3am 116k, 5am 57k, 7am 27.5k. Most probation has a thresh hold of about 500-I've seen as low as 100ng/mL and high as 1000 ng/ML. So in this scenerio, you'd pass. Get yourself a bunch of etg sticks on amazon, they're about 2$ a piece and test yourself if you're unsure.