CRBA Appointment Times Still First Come First Served?

Does anyone who has done this lately know if appointments on the day are still given out first come first served? I know when I went with my first daughter 2 years ago, we were told very helpfully by someone on this forum that you just show up on the day and get in line and they hand out numbers by who first comes through the doors etc regardless of what time slot your appointment was. Which was really handy cause we were in and out in an hour and a half and the guy behind the counter winked and smiled saying most people don't know that trick

Anyone know if this is still the case? Would hate to show up in the freezing cold on Monday with  a 6 week old baby standing around outside at 7am to get in and out fast if they won't see us until our time slot (which is 8:30 or later I think I have to check!)

Thanks!