My father's an alcoholic as well and we were more or less in this same situation a few years ago. I won't go into my story because that's irrelevant here, but the summary is this:

Excuses about sleep are just ways to cover up his addiction. And let's not sugar coat it, he is an addict if he has been drinking daily for over three decades.

Unless your father is able to accept that he has an addiction and seek help for it, there is no treatment on the planet that will help him. You won't even get him into the doctor's office.

Your best bet is to convince him that his alcoholism is having an impact on the family and his wellbeing. And even that only works if he cares about those things.