They did however start declining payments after about 3am and the card is now blocked / HSBC say they're going to refund it all which, in answer to @PhilDAS means the payments will bounce today and they shouldn't be processed. Small satisfaction.
Couldn't see it on the card or on the site at 1 in the morning.
Still have pretty empty accounts though! They went up to £7k in the end. Amusingly they made a £2k purchase at Evans Cycles. So it's basically someone on here.
Seemingly no 24 hour number! :)
They did however start declining payments after about 3am and the card is now blocked / HSBC say they're going to refund it all which, in answer to @PhilDAS means the payments will bounce today and they shouldn't be processed. Small satisfaction.