I've been the past 2 years to Universal during
HHN for 3 nights, and I don't go to HHN while I'm here (it's just not my thing, cause I'm a big Scardy Cat). I usually visit the parks for 2 days and spend the third at my resort. The park days end early cause they get ready for the HHN, but this has never bothered me. I find the park pretty empty during the day. I get to the WWoHP for early entry both days and am pretty much done with everything I need to see and do by 2ish (without Express Pass) when I head back to the resort for pool time. I wouldn't call myself a commando park person, but the past 2 Octobers I've been there the crowds have been minimal in the day - I assume HHN's are a whole other situation though. In fact, we'll be back this October and hope for a similar situation. Just wanted to share my experience in the parks during October even though we've not been for HHN.