Usually alcoholism treatment is most successful when the alcoholic themselves makes the decision to seek help. It rarely works when the alcoholic is entering treatment to please another person, or to save a job, or to get a drivers license back, or to stay out of jail.
This does not mean that supporting the alcoholic in their decision isn't important. It helps them to see and hear the consequences and pain that their alcohol consumption is causing.
The addiction to alcohol is a disease. Left unchecked, it will get progressively worse. Abstinence is the only real way to recover.
I tried cutting down, but was unsuccessful. It was all or nothing with me. It became unpredictable and I would binge drink whenever and where-ever I could.
Broken sleep patterns can stress people out. I did night shift for awhile and it was too easy for me to drink into the morning. Can he, or will he go back to working days?
Best of luck to both of you.