Function doubt_unread_with 

fn doubt_unread_with(
    knowledge: &Knowledge,
    due: i64,
    waking: i64,
    now: i64,
    missed: Option<&(i64, BTreeSet<String>)>,
    first: Option<&str>,
) -> String

The doubt, first said before what the devices leave unknown (a reminder that comes late, one another device may have shown): “Sioul can’t tell whether it was taken: …. Check before taking it.”; “” when nothing is. What looks back counts from the dose’s time, the opening for it from waking (sioul_core::health::doubts_at; the sixth review’s M1).