If you pass your home test using your first void of the day (The dirtiest) you should be good to go on the PO test.

EDIT: It will be much easier to tell what kind of chance you have to be legitimately clean if you tell us your previous smoking habits (in the past month/year) as well as your height, weight, and excercise habits.

Home tests are just as accurate as probation tests as far as THC detection goes. The only difference lies in the fact that home tests can be fooled by water loading much easier.

PO tests as well as drug tests for employment check for specific things in urine to determine it's validity. Primarily they test for creatine levels, PH, temperature, and specific gravity.

That is why it is much easier to fool a home test by just water loading your system, whereas if you take a test with your PO additional preparations must be made in order to dillute correctly and still have all of the other things they test for stay in check.

I'll say this again like i've said to so many others here. Do not risk smoking on probation, just roll with the punches and smoke when you get off probation.

If you decide against taking this advice then your only option would be the dillution method because it is very tricky to substitute during a PO test (they are monitored).

To address your immediate concerns, I would recommend getting a home test and testing yourself a few days before you meet with your probation officer to see where you stand (if you are still pissing dirty) And if that is the case then Follow the dillution sticky at the top of the forum.

If you have any further questions there are many regulars on this board who are far more knowledgable than I and will be able to assist you. If no one has gotten back to you I will be back in a few hours to answer any additional questions or concerns you may have.