Running a phase in backgroud

There are times when you have a system that allows testing different sub-systems independently, so there is a benefit in being able to run phases in parallel in order to optimize total test duration. For example, when you burn FW to one component, you can still test a different one.

From my understanding it is not a built-in capability and I wonder if this was previously discussed.
Is this capability aligned with the architecture or does it break it somehow?

Also, any idea to achieve it would be great.

Thanks.