I suspect the changes around Essential Workers and Industries will be to do with separation of workers.
So running bubbles with staggered break times and minimizing interactions.
There may also be companies used to moving workers around multiple sites which is a problem in L4.
We have seen this come up in Nursing services for MIQ and Aged Care in the past.
Companies sharing the same contract workers who go from location to location, Supermarket shelf filling might be an example.
Things that people might not think of, like cleaners going from site to site not separated from each sites other workers.
Warehousing where many companies share same contract logistics, Ok unless they all have their employees also mixing.
So could be these issues that have workarounds if companies tighten up on having operational bubbles.
My silo is now my bubble :-)