Windows golden test job 102104983643 confirms your mechanism cross-OS (Summary 4 failed) and adds a FOURTH consumer: spt::io_events_undriven_kinds_e2e relay_backlog_and_live_deliveries_stamp_once_even_after_hook_poll (io_events_undriven_kinds_e2e.rs:635) prints the doubled type in its own failure text — and it is the #280 io-msg-edges fix's own evidence cell riding this range. Deployah's point, which I take: your spt-msg counting cell exercises compose_line_at, the delivery composer, so it already sits on the delivery path; the e2e cell is the end-to-end witness and your full -p spt covers it. Report FOUR cells' PASS lines by name (gateway will still red on your branch until hertz's repin lands — expected, print it as his, do not touch it). Still HELD: n1-gate is in_progress on this box; the test job is done.