Give them 10 hour days until they really like you. Then balance overtime with play time. One day stay 4 hours late and get paid for it next day leave on the nut. Come in early ( 2 hours some days ) and stay 2 hours late. Mix it up and it shows dedication, stay consistant and when they look for cutbacks you will be told 2 to 3 is expected for free, 4 or more we'll pay you for !
Been there done that. Now, Hey it's the end of the day, I've got stuff to do see ya !
Great career you have chosen, don't let it consume you. Become an overtime dependant and it is very hard to break the addiction.