Bi and pan people are ALWAYS valid. No ifs, ands, or buts. No going "But what if they're with someone who isn't their gender!" Even if they're with someone who isn't their gender, their still valid. That doesn't change the fact that they're bi or pan. (more in next post)
And also, no shaming NB and genderqueer folks if they choose to present as the gender they were assigned at birth, whether out of a situation at home, habit, or personal preference. They're still valid, no matter what. It's just totally not right to claim they aren't valid for doing that.