There was an event for this film today and a bunch of information was released. You can read the Crunchyroll source here if you want all the details. Some highlights:

• There is an alternate “light” version of the visual as well and I had a hard time deciding which one to use as the lead image.
• Here is the new PV you can check out
• This movie is being made by a popular animator on youtube (channel here) named Gensho Yasuda
• The premiere is set for “summer 2024” in Japan
• Runtime will be ~90 minutes

AniList doesn’t have much of a synopsis yet, but Crunchyroll summarized it as:

The “cyber love suspense” film will take place in the not-too-distant future, where young science genius Akira Mizutamari has developed a helper robot named Salt. While he’s succeeded in commercializing Salt, all his other inventions crash and burn—until a friend suggests that having a girlfriend might help him “power up.” To that end, Akira engineers himself an android girlfriend, No. 0, who is programmed to love him. But over time, she begins to wonder whether or not her feelings are real.