X_SUPERSEDED

a later generation superseded this work

an answer came back for a generation the fence has already moved past — a reload, a resubscribe or a re-render whose predecessor finished late. Classified terminal, and declared rather than defaulted: re-running superseded work produces this same refusal by construction, so an unclassified reading would spend a job's whole retry policy proving that the world has still moved on

discard this answer and re-issue the work against fence.generation() — whoever called bump() has already started the replacement