Recently I picked up a project on Office 365 with a content type hub. I got some deployment scripts that were developed before by someone else. All the easy work left for me.
I created a content type hub I then activated the content type publishing feature and tried to publish my content types and I got a big ugly error:
No valid proxy can be found to do this operation
For the content type hubs Apparently on Office 365 a content type hub has been pre-configured.
There is a site at https://mytenant.sharepoint.com/sites/contentTypeHub
So you can then publish the content types on the site settings -> Site content type option