Why do you need a 99.99% from job completion rate? Why not just design for failure and inevitable retries? Almost seems like you grant platform users a false sense of security by making it very reliable but not perfect.
A lot of traditional financial instruments 1) are not resilient to failure and 2) run at fixed times in batches. I’m confident it’s not their own systems that set the requirement of rigidity.
Their customers expect the cron jobs to run when they expected and how they expected.
With that constraint restarts look a lot less acceptable.