Easy Drug Rehabilitation

A PSA about inhalants.

I was wondering how the random drug testing for a first offense oui for probation in Springfield Mass works? Like my friend gets a letter in the mail giving him like a week notice to come in to get tested. Or would they just show up at my house? I’m just wondering so I know what to expect.
how long do they usually give you to show up like a week or so? the reason i ask is because springfield is kind of far from where i live and its hard to get rides atm.