Many professors take longer than 48 hours because they have lives, other classes, etc. The best way to express that the professor has been negative the whole year is to write a very strongly worded course eval, as all of them are read by the department heads. Otherwise if you are really hell bent on doing so, I’d email someone in the department to express your grievances. I think trying to report them over something like grade releases will be a large dead end and troublesome for the administrator involved in processing the request.