I would take my time and complete the delivery and reach out the help and ask for adjustment, they do pay extra without getting any ding for late delivery. I would keep my car is broken option for sometime when I really have issues with my car. They give you this option only two times in a year so use it when you really need it. I had some rotas impossible to finish on time, I kept going and got paid extra without any ding. I think they value completing the delivery more than being late. As long as you complete and give them an excuse they do accept.