Originally Posted by btonkid12345

You paid for domestic first service. You will receive the hard and soft product of the service on the plane, and also get sky priority services (including the sky priority check in and security line) with the ticket.

Flagship first check in is only for international D1 (and perhaps the domestic transcons too). You can't just "head over" there; there is a security guy in a suit standing outside with a list of names. If you're not on his list (I wasn't) and can't show a BP with a seat in D1 (I was able to do this) you won't be permitted past the frosted glass doors. No chance you are getting in with a domestic first ticket.

Also, in my experience, the agents at sky priority check in at LAX are both more efficient and more knowledgeable than those I encountered at flagship first. Don't just believe the marketing hype!