I understand the evidence indicates that with long-term excessive long hours, performance is worse. You could be the outlier, able to work efficiently after ten to twelve hours, but I understand the probabilities are against this and that actually it is about perception; that the person in charge of saying how good you are at your job is effectively incompetent and can only measure time in office.
You can push back or negotiate the deadline. In my short career, I found that most deadlines are BS. They're just there because someone somewhere made the arbitrary decision that it needs to be delivered by then. There is no reason behind it.
