Although I've manually upgraded to version 2.1.3, in the error logs I'm seeing this error:
[29-Jan-2016 16:45:07 UTC] [WPMUDEV API Warning] No remote data found for project 136
[29-Jan-2016 16:45:07 UTC] [WPMUDEV Site Warning] No remote data found for project 136
On version 2.1.2, although I was being prompted that there was a new update, there was no update button available within the WPMUDEV Dashboard or the Network Admin Plugin panel.
This may be more of a dashboard issue. I believe I read in the changelog that this was fixed in a previous version, but I'm still seeing the error.