Selebus is posting previews even from vacation, so I think we should have this discussion right now or we could be just late for it:
Which girl would be chapter 4 cover
My primary bet is Sana: she was set up during this chapter, her route was forced (i.e.
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was skipable
, but
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wasn't), she is from first floor (it can be used as counter-argument as well, but netherless), she is set up to realy understand Sensei blackouts, which should be major chapter 4 arc. Also she is part of SLS now, where three first covers came from
Other bets: Makoto (doubtful, unless she would mmake it to the roof), Tsuneyo (second floor to balance first floor, her ability to keep memories through resets), Yasu/Nodoka (most doubful, but still possible)