After speaking with your support earlier today I found that despite having a support option for your REST API in the 365 Admin portal you have no avaliable trained staff to actually support the API. To ensure that nobody else wastes upwards of 30 minutes of their time on hold only to be fobbed off back to the very article you showed them at the beginning of the call to employ or train a collective of individuals in your call centers on the rest API or don't advertise that you'll support it.
Hi Ben, we are sorry you had a challenging experience trying to get support. I have passed your feedback along to the teams who handle our support.
For future reference, we also have a couple free support options:
MSDN forums are here: https://social.msdn.microsoft.com/Forums/en-US/home
The product group is very actively looking at Office 365 REST APIs here: http://stackoverflow.com/questions/tagged/office365. Connect with us on Stack Overflow. Tag your questions with [MicrosoftGraph] and [office365]. The contact details and recommended tags are available in the Microsoft Graph Frequently Asked Questions (FAQs)
Office Extensibility Team