There is no hard and fast answer: it would be judged on a case-by-case basis when the employee applies for unemployment benefits. Generally, being terminated for not showing up to work is considered termination "for cause"--absenteeism--and therefore grounds to not receive unemployment benefits. But your question posits that 7 days/week is not the employee's normal working hours in the sense of being the hours that he/she "signed up for" in taking the job, but rather are additional, unreasonable hours added after the fact. An argument can be made that increasing hours beyond what the employee had effectively  agreed to work by a factor of 40% would constitute "constructive termination"--being forced out by conditions that an objectively reasonable person would find unreasonable--akin to how it is constructive termination (and the employee can get unemployment) if his/her salary/wages were cut by a third or more and he/she quit, or he/she was transferred to a new location resulting in a two or more hour each commute (when previously it had been, say, 30 minutes). So there are two different paradigms at work here--absenteeism, which is termination for cause and no unemployment; and constructive termination, or leaving due to objectively intolerable conditions, which allows resignation while receiving unemployment. The unemployment office would have to consider the facts of the situation and judge which paradigm it is more like in the individual case.