Reception Timeline

My wedding is at 3:00 w/ reception immediately after in a 100 year old civic/city meeting room. We are having cocktails, appetizers and music for guests while we take photos for about 45 min. After ceremony. If we want to open buffet dinner at 6:00 - 6:15 p.m., what do we do for that one hour between the time we arrive at hall and dinner is opened? Thanks so much for your help!