Ah, what the heck - nobody else has responded yet. There's a specific point in the script where Ryan and Alex are talking to someone else within their presence other than to each other. This happens to be Natalie and it's interesting because there's a certain subtext that is missing when they're talking to each other. When Ryan and Alex do talk one on one, it's like a mating ritual where the birds do their dances to one another - but when a third party is added here and someone is forced to discuss matters with them in the other's presence, it's like we get a different glimpse of the individual speaking. On page 62, when Natalie asks Alex about her type. Alex proceeds to rattle off a number of things, punctuated by Ryan smiling. We sense she's talking about him, his smiles and reactions being part of that flirtatious dance. When we have her reveal of being married - all of this very well could be carrying subtext to her marriage, particularly the points made about income. It's the one thing she seems to be directly speaking with experience. As for callbacks, there's what Natalie says to Ryan in her "cocoon" speech, about if she had that many miles, she would just pick a place and go. While the dialogue isn't repeated, the scenario is at the end of the film when we see Ryan doing just that. Aside from that, there's the much discussed Ryan statements that express his values with particular regard to luggage and relationships. Much of his values are exemplified through dialogue, the economy of how he lives... the notion that moving is living, etc.

[...] and Analysis Series: “Up In The Air” – Characters (gointothestory.blcklst.com)GITS Script Reading and Analysis Series: “Up In The Air” – Dialogue (gointothestory.blcklst.com)Young Adult (2011) by Jason Reitman (vertigostare.wordpress.com)GITS [...]