Function output_now 

pub(crate) fn output_now(
    fs: &FileStore,
    zone: &str,
) -> Option<(u64, Option<String>)>

output’s size and valid generation, from the database — never this process’s stat cache, which another srv instance’s append makes stale. A counter only behind (an older build appended since) is caught up first, so its generation holds across those appends (filestore/counter.rs).