Drug testing for CDL's is federally mandated so it will remain illegal till the federal laws are changed. Your 2 year physical will just be a urine test for blood sugar levels, no drug testing. You won't be drug tested till you are being considered by an employer.
Subbing with synthetic urine is an option. I've used it numerous times. You will need a plan to beat the randoms. They're getting trickier with DOT tests. Some companies are contracting with testing companies that come right to your truck and test you.