Well....as much as I enjoy possessive neulbin, if we're considering cannonverse I always saw them as being kind of open (while still being mutually possessive) for the sake of pragmatism.

From just like a kinda petty/take it in stride perspective, I could see Hao just kind of being like, "what is there to be jealous of". You know? Like passion and enthusiasm can only take gyuvin so far with hanbin. Because that boy loves competency, which Hao has in abundance. He wins the war not the individual battle so to speak.

But overall, I think that wanting what's best for hanbin / not denying him what he needs would win out over possessiveness for Hao. Like it's very clear that Hanbin gets something very specific and very treasured from gyuvin.

And I mean for that matter, I sort of feel like gyuhao is a very intetrsting duo. Like it's easy to imagine these two clashing, and yet they seem to be really comfortable with each other. I like to imagine them getting there over time, as trainees.

Maybe clashing, but gyuvin being younger and lost, and from a shipping perspective having to figure a lot of stuff out and sort of colliding into Hao and making him a reluctant mentor. Its not hard for me to put hao in a similar role i put hanbin in for gyuvin. An aspirational, but confusing figure. Someons he aspires to be like, but someone who forces him (probably a lot more bluntly and directly than hanbin would) to confront things hes not comfortable with about himself...

Not to mention these two have experience "sharing" a shared treasured human via ricky (you could probably sub in other yuehauz here but this one maximizes the yaoi, amirite). So, i think it wouldn't be hard for Hao to see that gyuvin needs hanbin too.

I view the vacation 100% as a "he needs this, and needs us, and it's bigger than me" kind of thing tho.