I am planning a trip to Copenhagen and notice that most of the beer bars do not open until mid-afternoon (typically, 15:00 or 16:00). Some are closed on Sundays. I will arrive in Copenhagen at 12:00 on a Friday. What is a thirsty beer tourist to do... sit in the Tivoli park and drink from the bottle
Øl & Brød by Mikkeller (http://www.ologbrod.dk/) is open from 11:30 on Friday. It is 500 meters from the central station.
Have some lunch then hit Mikkeller Bar at 13:00. Or alternatively, Brewpub Copenhagen is open at 12:00.