Hi there.
I'm the primary partner to my nesting partner and husband, Adam, and the secondary partner to my Puck, who lives with his wife. Ours is also a long distance relationship which has been royally screwed up by Covid.
Guidelines are for communication, but there are some similarities and some differences in what I tell each person.
I, as their hinge, manage logistics around who I'm spending time with and when (obviously this includes "phone" time). Puck and I have access to each other's Google calendar, and Adam and I have a calendar on the wall, but that's mostly for dealing with other things like our out of town friends visiting.
With Puck, we are quite flexible about rescheduling things when local life gets busy. We aim for as much warning as possible.
When Adam and I have a date planned, we stick to it.
I tell Puck about anyone else who catches my eye. With Adam, I only tell him about someone when it's getting serious, although I'll talk about my (guy) friends and the friend things we do. Like, if I'm out with anyone for any reason I'll tell him where I'm going and when I expect to be home. Just normal stuff.
I'll tell Adam regularly about where our joint finances stand, since I manage them. I'll tell Puck once in a while about the same. And vice versa. When international travel is possible again, there will be more financial planning to have at least one trip a year, either me there or him here.
I'll tell them both about any health things that come up.
They have the means to contact each other (in case I can't) and have said hi on the phone before, but because it's long distance, traditional kitchen table isn't feasible.
I would expect Adam to contact Puck if I couldn't, this is an absolute hard limit of mine in poly. I trust Adam to completely. And when I can finally visit Puck post Covid, he knows full well that Adam is my emergency contact and would call him unhesitatingly.
Adam is my default sole beneficiary if I die first and Puck is not in my Will for division of estate if I outlive Adam, but that's because I've named some younger people, instead, including Adam's children. However, if I died early, Adam would send some things to Puck.
Occasionally, I complain about one of them to each other, but it would be when something is affecting my well being that I can't stop spilling over a little. But most of the time, both relationships are calm and strong, so there's no need.
I hope this gives some insight into the things that I place as top priority communication. Feel free to ask questions.