Fall Out Boy - Saturday Lyrics Meaning

Its very likely about the thrill of playing a show and how they cannot wait until the next, because when you go to a FOB show, they always play Saturday last.

Yeah I think 'Astoria' is probably referencing the gig venue in London, it used to be (before it closed down) a VERY famous venue, if a band played there they had 'made it' kind of.

Also, I think "and I'm coasting on potential towards a wall" could mean he has so much energy and has put so much into it, and the show is the wall, where all the energy has to come out, they have to show how good they are.

"ive read about the afterlife, but ive never really lived more than an hour" could be that he only ever truly feels alive when he is playing a set onstage (with a show being about an hour long).