Is the workaround likely to be known to most call centre agents that have been there a while? - I ask as the guy was fairly certain I was in the wrong until the LHR > SLC "trick" got him to think rationally and double check with someone and I'd of hoped he'd of offered to perform any workaround just to make himself look less incompetent but he didn't. I guess he just wanted me off the phone by that point in time.