Can I get an INTERIM clearance/public trust with past marijuana use?

I’m considering applying for jobs that would require either a clearance or a public trust. I smoked marijuana in the past and stopped about 18 months ago. I’ve done some research and I’m getting the sense that I might be able to get a public trust or clearance even with past marijuana use, especially if I wait a couple more years before applying.

However, I know that nowadays a lot of clearances are approved on an interim basis so that the applicant starts work while the clearance process is finished in the following months. And I’ve heard that it’s much harder to obtain an interim clearance than a final clearance unless your SF-86 is spotless. I.e. drug use in the past seven years causes an automatic denial of interim clearance.

Is this true, and if so is it true for interim public trusts as well?