I totally get this reason. Does this work somehow like Gibraltar(where Wave Crest Holdings Ltd. is registered) is a part of UK but not really?

So it can issue cards and give you more freedom with it than your local banks? And BitPay makes it much easier to get card from them, right?
I'm not sure how Wavecrest were operating, but they certainly ain't no more. There must have been some type of Gibraltar specific kludge that they got up to.
I'm not confident there'll be another GBP card. Perhaps somewhere like the Isle of Man might but they'll be more dependent on UK banking. The Isle of Man is similarly not quite in the UK like Gibraltar.