I am on a mass program and have been on Creatine for about 5 weeks. Is there a time where I should cut back? Is it best to cut back on a cutting phase or keep it a constant throughout?
Not sure on that but Lyle McDonald suggested that you not take creatine while on cutting phase… It depends on what your cutting diet is like. If it’s low carb, you’ll be running on low fuel and taking creatine would make you work harder but you’ll be more sore and take longer time to recover.
Lyle McDonald - now there’s a blast from the past. LOL 
Stay on the creatine. If anything it will help keep you from losing muscle during your diet. Plus you’ll have better workouts thanks to more available ATP, providing better muscle stimulus - further preserving your muscle.
Why’s that?
Cause you’ll be working harder.
Doubtful. If you’re dieting hard your performance will dip anyways - taking creatine will help keep that performance level up - it’s unlikely that it will have such an effect that you’ll take your training levels above and beyond what your body has already adapted to in a non-dieted state.