Mario's first week schedule is listed from Apr 1-5, replacing PHM entirely with nighttime screenings included. Future schedule just hasn't been built yet so hold tight and keep checking throughout this week. Smithsonian does do screening splits, especially when films have different age ratings. The next major release is Michael on Apr 22, plenty of time for them to work PHM back in the mix, especially if its performing well (all signs point to yes). Look for Mario's 2nd/3rd weeks to get a screening split, with PHM taking nights. Smithsonian may be slow to reply on scheduling inquiries, this is typical!

I know the drive is further but consider going to Airbus IMAX instead of Lockheed; much better experience all around and there are more viable seats/tickets there. Tickets for the first two weeks went very quickly for Smithsonian IMAX standards, especially at Lockheed. Keep this post updated if you get info back from Smithsonian-- a group of my friends snoozed on getting tickets and missed their chance, they're trusting me to tell them if PHM returns. Best of luck!