The rules state"means an amount of cannabis, derived solely from an intrastate source and

in a form approved by the department, possessed by a qualified patient or collectively possessed by a qualified patient and the qualified patientā??s primary caregiver, that is determined by the department to be no more than reasonably necessary to ensure the uninterrupted availability of cannabis for a period of three (3) months.
An adequate supply shall not exceed six (6) ounces usableble cannabis An amount greater than six (6) ounces usableble cannabis may be allowed, at the departmentā??s discretion, upon proof of special need as evidenced by a practitioner letter explaining why a larger dose is indicated. Any such allowance shall be reviewed for approval by a medical director designated by the department, who shall consider standards for exceptions to the adequate supply requirements that are approved by the advisory board." The reason is not that you are using more than2ozs a month.In this case it is that you need to have a 12 month supply.Also the six oz. limit at any one time is a problem if you want to make edible you will need at least1-2 ozs per pound of butter. So that would leave you with 4 ozs to last you 3 months.Now if you want to make the "cure" which is an oil you would need up to a pound of product.This is an area that needs to be redone with a better understanding of the needs of a patient.