Builds stalling on all platforms (most of the time)

Description of issue:
Our builds are stalling, and then being cancelled after 2 hours. Except the odd desktop build which succeeds.




Unity version: 2017.1.0p3
(We installed 0p3 which fixes iOS ILCPP errors)

XCode version:
N/A as stalling on multiple platforms.

Source control:
Collaborate

Local build platform:
Windows + Mac

Build target:
Windows, Mac, iOS, Android

Relevant plugins being used (i.e. Google Play Game Services, other plugins that may perform automatic post-build behaviors)
Facebook SDK, Odin Inspector

Project name:
Blackout Rugby

Build logs (relevant chunk unknown, that's why we've resorted to forums for help):
Last line which it sits on for the last hour or more is usually this, except with Android:

Code (CSharp):

1. 210: [Unity] Begin MonoManager ReloadAssembly

Here are links to full logs:
Mac
Windows
iOS
Android

Does it build locally from a fresh checkout? (Instructions below):
Yep. Although you could probably make it easier to download a fresh copy of the project via Collaborate. Minor suggestion

 

Thanks @dannyd. We'd love to upgrade to 2017.2 but there is a critical performance bug with UI which my colleague has posted about here. As soon as this is resolved, we'll upgrade in a second.

In the meantime we may look at possibly downgrading from using C#4 but it would take some time, and there are some really valuable features we'd miss. But then again, it'd stop unity from crashing frequently so that's a pretty big reason.

I'm curious though, our builds worked fine previously on 2017.1. Has something changed in the cloud build process?

 

Not sure I follow.

Just to clarify – our build history in UCB is quite stable in 2017.1. It's only recently started stalling, in the cloud only.