When should you handcuff RBs?

I have Mixon and Montgomery as my running backs. I am mostly worried about Mixon going down. Team for reference

If you want a handcuff, I feel you could drop Hines But I wouldn’t be concerned about Montgomery. Mixon could be questionable.

I just saw I still have AJ Dillon on waivers which is making it harder to decide

I would drop Fields for Dillon. You wont likely ever play him over Russ except for a bye week in week 9. I suspect you could plug and play a waiver pickup for that week.