"It’s more the lying about it and hiding it."
This is a bad argument to make to someone who dependant, unless you're not going to get in a mood when they fail.
Distraction is useful if you want to help him, you know the risk time for him so perhaps find something he enjoys doing with you you can do at that time.
Ie go to bed at the same time, maybe start late when he normally goes than together work forwards to your bed time
"Small beers" are another good one it's not thier size it's thier percentage it refers too about 0.5-2% and they're brewed for that percentage unlike low alcohol beers which are brewed higher then have thier percentage reduced which can taste bad.
It will give him the sensation, and fill the habitual habit to drink but reduce his alcohol.
He can have his 4 or 5 a nice but only really be consuming as much as 1 or 2 depending on his normal drink.
Won't lie to you and say it's easy it's hard, and he'll be moody and uncomfortable through it and that will strain you and your relationship.
It's up to you thought to decide if that's something you're willing to take on or if the relationship isn't worth the harm to you for however long it will take.
Ultimatums really don't work thought "it's me or the beer" will just translate to more hiding behaviour