Baggage Question
 

Had separate tickets (AM Mex-Mia), then DL Mia-Atl. Had Mia-Atl boarding pass in Mex, but couldn’t convince agent to check bags all the way. Is this normal? Also, (apparently there is no Priority line [MENTION=46685]MEX[/MENTION]) not that I could find -only the herd line.

You have to pick up your bags when arriving on international flights upon entry to the US when connecting to a domestic destination and going through customs. There's no way to check them all the way through without you having to touch them if that is what you are asking (even if you get them to tag it all the way through).

Of course there's a priority line. It's it's own section to the far left side with lots of signage (side by the train). They handle Sky Priproty for all flights on AM including US.

I cant speak for AM, but if you were on DL it wouldn't have been an issue. Each airline handles different.