Prevent confirmed subscriber becoming unconfirmed when re-subscribing. Closes #2987

Author: blu3id

queries/subscribers.sql

@@ -189,11 +189,12 @@ INSERT INTO subscriber_lists (subscriber_id, list_id, status)
     SET status = (
         CASE
             WHEN $4='blocklisted' THEN 'unsubscribed'::subscription_status
-            -- When $11 (allow resubscribe) is true, override existing statuses (used by public subscription form).
+            -- When $11 (allow resubscribe) is true, override existing statuses except confirmed (used by
+            -- public subscription form).
+            WHEN subscriber_lists.status = 'confirmed' THEN 'confirmed'
             WHEN $11 = TRUE THEN $8::subscription_status
             -- When subscriber is edited from the admin form, retain the status. Otherwise, a blocklisted
             -- subscriber when being re-enabled, their subscription statuses change.
-            WHEN subscriber_lists.status = 'confirmed' THEN 'confirmed'
             WHEN subscriber_lists.status = 'unsubscribed' THEN 'unsubscribed'::subscription_status
             ELSE $8::subscription_status
         END