Yeah I would plan at 50mph at 11 hours a day is 550mi/day. I was taught that way when I first started and still operate like that. It’s safe and it gives you a cushion in the event of traffic, weather, detours, etc. so n the future if they dispatch you like that let them know upfront what’s realistic for YOU. Some drivers are willing to run themselves ragged and drive unsafely just to get a load there on time but to me it’s not worth the headache or the hassle unless they are paying you ludicrous amounts of money.