What is the mechanism in Prefect 1 to support a restart?

When a workflow is interrupted due to a manual shutdown or a crash, is there a mechanism that would allow the flow to continue right where it was before the shutdown.
First in Prefect 1.0?
And if not applicable in Prefect 1.0, how about Prefect 2.0?

For example,
Flow:
task1: do something
task2: create an asynchronous job that will sleep for 1hour

When the task succeeds, the flow succeeds.

While waiting for the task to complete, there is a manual shutdown or a crash. The job continues to sleep nicely.

When the container is restarted, is it possible to have a workflow that would go straight to task2, without running task1. And when the job completes, the workflow ends successfully.