It doesn't look like there is currently a way to enable/disable a content-based entitlement (i.e. PE code) via the API. Is that actually the case, and if so, are there any plans to support this in the future?
Do you mean you want to change user entitlement via API?
If it is then, no, Open DACS API is not designed for administrative purpose. The goal of Open DACS API is to allow authorization checks to be performed outside the scope of TREP.
You can perform authorization checks using Open DACS, but you cannot change use permission.