-returnLicense flag does not work anymore since 2018.1

Hello there.

So, apparently the -returnLicense flag is broken since 2018.1. I've tested it in multiple devices, in multiple networks and I'm always receiving the error below:



This happens with or without batchmode (on batchmode this error shows up in the log only, obviously)

Returning the license manually through unity works correctly, trying to return it via command line always fails, no matter which combination of flags I use (-nographics, -batchmode, etc).

This seriously hinders the ability to use our CI system that relies on being able to activate a license and return it as needed, what can be done about that?

Would there be any hidden function we can call to replicate the GUI behavior with -executeMethod as a workaround for now?

This worked properly in the 2017 cycle, btw.

Thanks for your time.