Job hangs but only when run from cron

I have a series of jobs that pass when run via push, but when run during a weekly cron job they fail on the OSX environment. The jobs start out by installing a python Anaconda environment by using the tools from ci-helpers (https://github.com/astropy/ci-helpers). You can see one of the failing jobs here (https://travis-ci.org/pytroll/aggdraw/jobs/540157729) which seems to be hanging during the git clone step of ci-helpers. The script doing the cleaning can be found here: https://github.com/pytroll/aggdraw/blob/master/ci/travis-install.sh#L4

In the past I’ve had trouble with ci-helpers mistakenly setting set -e which was causing issues with travis, but this time it looks like I’m not even getting to the ci-helpers part of the process. And this is only happening during the cron job. Any ideas?

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