Hey @Rob Fowler, congrats on the job change! On the first post, I feel like it can be done in current Prefect. We can have long running tasks. You can construct this as a Prefect flow using the ShellTask and reading the outputs of the ShellTask, and then doing those forks and exits.
With regards to Orion, there is nothing there is supporting the long running task execution. But, it may still be a better fit because of the better handling of subflows, allowing you to have more modular code. That 5000 line shells script can likely be broken up much better.
On the second comment, the Flow being a short running process, that can also work. On the Prefect side, we don’t care about execution time anyway. Just an idea, but you can maybe also use manual triggers to check on the status of Flows and trigger the continuation from day to day.