PAC REST API available?

Is the PAC REST API available on Epic? I need to have access to variables and IO on remote units that are part of the control program.

Yes. The RESTful interface is up and running on EPIC.
Plenty of help in the forums, but if you have any questions, just ask.

https://forums.opto22.com/search?q=epic%20pac%20rest

The key to getting it going is to have /pac/ in the URL like https://epic-hostname/pac/device/...
If you need more specifics there’s a PAC API reference on the developer site as well as the info on the forums.