TLDR; Chika might be first to die
I love that psycho/yandere Ami is confirmed now. I also like how many theories that people have had before are slowly being confirmed, and kind of have my own long shot theory about Ami.
Since she's killed before, ("butchered" definitely means killed in this context) then the top 3 candidates for Ami to go after would be Chika, Ayane, and Maya, in that order. I figured Ayane would be number one months ago when i assumed correctly that Ami was a yandere, because of Ayane's obnoxious love for Akira, the lost child, and how Ami reacted to finding out that Ayane knew of the true relationship between Ami and her uncle, but .31 makes me think that Chika might be first. That's definitely how things seem to be lining up. There's already a high chance that Chika will end up in the new apartment complex with Akira, either a few doors down like Touka mentioned, or maybe his exact unit. But now there's the likelihood that she'll end up working at the maid cafe that he frequents regularly, putting her in close proximity with Akira on a regular basis. I think it might be plausible that Ami and Chika might have a confrontation at the maid cafe while both trying to cater to Akira and Ami goes overboard, resulting in Chika quitting on the spot out of anger and not being able to work with Ami. (It's a long shot I know, but I feel like it's plausible.) Chika has already spoken of how she thinks that Ami loves her uncle a little too much multiple times, and due to Ami's rebuttals and other statements regarding it and around the time that Chika has spoken out, has left Chika in a less than stellar moods on occasion, as we saw in this update as well. I feel like these multiple occurrences and verbal clashes have been building up to something, and I believe Chika's soon to be employment at the maid cafe will exasperate things further. If Chika quits on the spot like I mentioned earlier, that of course wouldn't sit right with Akira, and he may demand Ami apologize for her actions at the cafe, not only because he thinks she's gone too far, but because it would put Chika and Chinami's well being in jeopardy. That might be the final bit needed to make them move into the new complex since Chika would be out of a job and have no way of keeping Chinami safe and a roof over their heads.
With all of that said, I can't think of a good way of Ami finding out that Chika's staying there, but her finding out coupled with her employment (proceeded by her unemployment) at the maid cafe would bring her to believe that Chika is purposely placing herself in places to be close to Akira. Finding out about the secret apartment along with this would lead her to speculate that either her uncle and Chika are secretly seeing each other, or that Chika's plotting exactly that. Since Ami has already heard of the resets from Makoto this reset and has shown signs of mentally/metaphysically cracking, I believe this Chika situation would be the fuse igniting that pushes Ami over the edge and get her to go after Chika.
That's not even mentioning that if she finds out about the secret apartment and Chika being there once she is, she'll more than likely find out in person at the complex by following Akira there (thought of a way for her to find out about the apartment that makes sense), leading her to also possibly finding out that Chinami sees him as a father figure and always calls him papa, making her believe that Chika is her lover replacement, and Chinami is her daughter figure replacement. Remember, she just went on an exposition about how if she's apart of Sensei, the same way organs are, that he could replace her just as he would an organ if it wasn't of use to him anymore/stopped working as intended/wasn't what he wanted anymore (whichever way she worked it), and asked if he'd replace her if that were the case. Although a long shot, that all would directly correlate with a lot of what we just saw this update.
Any thoughts?