Eventually.
Officially there is no downgrade path to those on Office 365 that have installed 2016 (i.e. there is no going back). But it can be done by contacting Microsoft Support directly via the answers desk and either have them remotely access your PC, or ask for
a link to office 2013.
You'll need to uninstall:
http://support.microsoft.com/kb/2739501
Though I had to do the total manual uninstall here as the normal uninstall left components there which prevent 2013 reinstalling:
https://support.office.com/en-us/article/Remove-Office-2016-or-Office-365-4e2904ea-25c8-4544-99ee-17696bb3027b
Lost all configuration changes and settings and it was a complete hassle, but at least now I don't have pen ink disappearing.
I'm astonished at this failure by Microsoft. Not only was this a well reported issue in the preview version, but it is on Microsoft's own PC, their own latest operating system, and their own Onenote software, yet they still released this software with this
bug that makes Onenote fundamentally useless for the key purpose it is marketed with the Surface.
So apparently, Microsoft, the world's biggest software company can't get their own software working properly on their own PC that runs their own operating system.
It would be good if someone from Microsoft gave some explanation and an update on this.