I was just on CO6 last month and things got a little crazy after the BF call. Plenty of non elites were trying to board during the elite call.... BUT I applaud the gate agents for sending the non elites back and stating this was elite boarding only.

Side note on my NRT trip: The walk to the ANA lounge is well worth it compared to the PACKED UA lounge. I do realize the UA lounge is right next to the CO departure gate... but if you have more than an hour to burn I suggest the ANA lounge. ^

The noodle bar alone is worth it alone! (and great views)