Stacking SEMA and RETA

Hello all, I’ve been on SEMA since August. I’m down 60 pounds so far, but still 60 pounds away from my goal. I have plateaued these past couple weeks. I’m interested in stacking. My question is what dosage should I start out at, and should I dose both at the same time or do one then 3 days later do the other? Current SEMA dosage is 2.5mg. Should I dial that back to 1mg?