Don't believe IG. I have an account many years ago, at least 4 years. When I login recently, they refused and asked me to open a new account. When I ask for a withdrawal to my bank account, the first answer is that "you are new client, we can only transferring back to the source, credit card".
My god, I understand why they asked me to open a new account. I forward all the emails from IG to prove I am an old user, then they said "that account is inactive, and we are not sure that account belongs to you or not" .
See ! When you stop their excuse, then they have another one. OK, I insisted I am an old user, he said he cannot transferring money to another account because of regulations. Haha, then he said after the initial deposit is cleared with the credit card, the remaining balance could be transferred to the savings account. MY GOD HAHAHAAAA, why at that moment you can verify two accounts from the same person
All in all, you can see that IG works closely with credit card companies. U transferring money from the card, they charge you, and the fund have to be transferred back without paying you back the charge. So credit card company can make money without costs