Yeah p*** poor from OCUK, they should bump you to the top of the queue, but looks like they would rather sell your card to someone else at inflated prices. In which case, ask for a refund to the amount of the replacement (£719), citing exchange rates and brexit
The more I read the more I'm disappointed with OCUK. I did think they were excellent, but this whole price gouge exercise has seriously made me think I will just buy from whoever is cheapest going forward, as customer service was the main reason I didn't mind spending the extra. Really, if they have one of the largest buying power in the UK scene, there's no reason they shouldn't have the best customer service and be the cheapest place to buy from (as opposed to consistently being generally the most expensive!).