Tarmaceater:
The issue with rest mode is you were not free to dispose of your time and didn’t know when the road would clear to move on again.
I have seen drivers fall asleep on their bunk when waiting to move on after a fatal accident, the road opens again and then stranded in lane two with all the traffic whizzing past and around .
The bed symbol or rest mode is also break mode
Break does not have the requirement to freely dispose of time but simply means time to recoup