Not entirely in the sense that you’ll still get authentication issues when EGI is down.
execute_batch indeed sometimes fails due to authentication or some other server unavailability, but in that case, the job can still succeed, and be inspected with:
job = connection.job(job_id)
job.status()
(which will still give you an authentication exception when EGI is down)
Anyway, for a more technical discussion and solution proposals, see this issue: