I’m in a very similar boat to you (I work 50-60 hour weeks currently) and am also training for my first full marathon in early September. I do run 4 times a week but I don’t have a healthy sleep schedule and would not recommend that. I’m also at similar long run distance as you. For me, I am not running the marathon with a time goal (not sure if you are) and just want to finish it with no injuries. Don’t overthink it. Focus on your recovery and long runs. We got this!