Welcome,
My husband and I had almost exactly the same routine, a few drinks after the kids were in bed, sometimes one while they were still awake. My co sumption seemed to co it use to increase, where my husband's although probably still more than he should be drinking stayed the same.
I finally managed to quit for good, I haven't had a drop of alcohol since NYE of 2015. I struggled in the beginning because he was still drinking. I needed to create my own new nightly routine. You have the opportunity to do that with your husband since he is sober too. Take advantage of that. Find a show you both love, play a silly board game, talk about the kids, work, crazy stories from the news. Recreate your evenings together sober. I can't wait to hear about how amazing they are!