We'd discussed this on IRC awhile back, and if I recall correctly there wasn't a lot of Sheriff demand for it - but we could consider adding a keyboard shortcut eg. (ctrl+b) or (shift+b) to Backfill the selected job. This would provide similar functionality to the existing ('r') to Retrigger a job. We currently consume ('b') for add a related bug, which wouldn't need to change.

Let's wontfix this for now since the sheriffs haven't said they'd need it.