Yes it is. No one would force you to leave. Only to take the break and relieve you from your duty.
There is bad info in this thread. I’m just giving the correct info. Some, maybe even most seniors will stay in delay. Some will require breaks. This can be enforced and is consistent with policy and the law.
Think about this. If the senior requires a break and 98 of 100 comply, what should be the consequence for the other 2? Not all of the other 98 wanted a break. I contend it is insubordination and failure to follow directive. Completely unfair to the others.