It’s a great question! If I had to guess, I would think that they might skip HMH this year. My only basis is that they delayed putting up Halloween decorations at WDW until mid/end September, even though they were well open during the time frame they usually put them up (mid-August). So DL will likely open with no Halloween decorations (unless they open VERY close to Halloween) and then add them in later. And it doesn’t make sense to open HMH without Halloween decor in the park. Also, CMs are still furloughed and they have a bunch of staff that assist with making HMH into what it is, so I don’t think it will open with it. Also, the few weeks of downtime it needs to transition to and from holiday may not be worth it this year when the parks have been closed for half a year and now APs will likely need reservations to visit and it’s not a leisurely “pop in” type thing. It would be a bummer if that ride was closed for a few weeks and that was when your reservation was.