It surprises me how few people who should know better don't use a proper TA especially those who know BArb are crap, and have the beans for fancy statuses. There's a small ticketing fee, but you can completely avoid having to deal with the airline.

A WhatsApp message and you'd have been rebooked to another confirmed BA flight -3/+14 (standard guidelines). If you wanted OAL (with UN only) the TA would call BA and get approval. There's also the scope to do WL before the ticket is reissued.

After the fact, it's surely a regret to have not spent £30-35 to avail of the service. At the end of the day, the BA Blue who paid for a TA will get rebooked faster than some pax where it suddenly dawns on them that status is worthless while they wait in the queue (if the line can even get connected). The faster the access to the GDS, the faster the rebooking.