I think that everyone works out what works best for everyone involved. For instance, MrS and I tend to have routine times that we check in with each other during times when we are apart (not a poly thing, just our thing). For instance if he is out with friends he will call around 11 pm (plus or minus an hour) and let me know if he is coming home or crashing elsewhere, tell me to go to bed (I am bad at this) and "tuck me in" by phone.
I don't think this would change if he were out with a girlfriend rather than his other friends. At the same time, those nights he is elsewhere I don't call/text him because I don't want to interrupt his evening - the same would apply, I imagine, if he were out on a date. The flexibility of timing ("touch base sometime before midnight") allows/would allow him to choose the best time/place to make the call so as to be the least intrusive to whomever he is with. (Say, while they were on their way from the show to her house or whatever...)
Other people have agreements about times that cell phones are off or that they are unavailable to others. I would think this would go both ways. For instance - she doesn't call at dinner or during "family nights" when he is home. And he doesn't call/text you during "date time" but then calls to wish you goodnight.
Just some random ramblings on the topic...
PS. We are not big text/phone people so our preferences might not work for people that are used to being in constant contact while not physically present.
Me: poly bi female, in an "open-but-not-looking" V-plus with -
MrS: hetero polyflexible male, live-in husband (24+ yrs)
Dude: hetero poly male, live-in boyfriend (5+ yrs) and MrS's BFF
SLeW: platonic girlfriend and BFF
Lotus: "it's complicated"
+ "others" = FBs, FWBs, lover-friends, platonic G/BFs, boytoys, etc.
My poly blogs here:
The Journey of JaneQSmythe
The Notebook of JaneQSmythe