An ADR is not like a "traditional" reservation. The restaurant isn't actually holding a table ready for your party at your ADR time. When you check-in, you put on the waiting list for the next available table for your party size (after the guests with ADRs that have check-in before you). So, the wait can be anywhere from none to as much as 45+ minutes after your ADR time depending on the parties ahead of you, how busy they are, if they're running behind schedule, etc. In general, I've usually had to wait about 15 minutes after I've checked-in to be seated. I have waited close to an hour at a few places (Citricos and BOG). For Akershus, you also have to wait in line to take your photo with Belle (usually), so that adds to the post-check-in waiting time.