I have a hard time seeing the line too. I think it moves lol. I've given up on distinguishing hypo from full blown and just try to look at the thoughts, emotions, behaviors, the effects of them, and the trend they're going in. (Going back to when I had a pdoc) if everything was manageable, no one was complaining too much, I wasn't doing things that are ridiculously risky, things weren't escalating quickly, I'd wait until the next appointment if it was within a couple weeks or otherwise move it up and set in some harm reduction things into place until then. If I knew I was going to hurt myself and/or others (or already have), it'd be a trip to the ER. If I was in the middle it'd be a call to the crisis line (the one that was just my old ACT team and they knew me and had an idea of what was the best thing to do).

But I know it's hypomania when I'm just running around, feeling consistently ecstatic, finding myself more impulsive with pleasure in mind (normally it's self destruction!), sleeping every nights at least 2 hours, making grand plans for the future that could be realistic for a healthy go-getter (probably not for someone on disability who gets shoved into a hospital involuntarily almost every year). It's obvious mania for me when I do a lot more dissociation and am completely disorganized. Self-care goes out the window, sleep is more erratic where I stay up 3 days straight and crash for half a day and stay up another three days, repeat. I feel totally out of control, sometimes doing something and immediately being shocked wondering why tf I did that.

Those are basically my extremes. Sometimes it's more obvious which one my current state is closer to, but unless it is clearly hypomania or clearly full-blown mania, I don't really put it in a category. I just say I need to be careful and get help (if that's even possible).