Function requeue_retryable_now 

pub async fn requeue_retryable_now(
    conn: &mut PgConnection,
    course_id: Option<Uuid>,
    course_module_id: Option<Uuid>,
    limit: i64,
) -> ModelResult<i64>

Makes every due-later failed_retryable row due now; returns how many. The button pressed once the study registry says an outage is over.

Only failed_retryable: no other state’s backoff means “waiting out an outage”, and submission_uncertain must never be swept forward in bulk.