Large positive balance on CC from balance transfer?

norm_

I signed up for the Halifax CC with the intention of using it for a money transfer, however I was told on activating the card the option to carry out a money transfer isn't until 3 to 6 months.

In the past I've created a small additional positive balance when carrying out a balance transfer and most companies have been okay with refunding that balance by bank transfer, with the exception of Santander who refused it.

If I transfer a much larger sum to a credit card from a much better bank that I use regularly, am I likely to breach some T&C and risk them closing the account, I looked at the terms briefly and couldn't see anything, or will they simply bounce the balance transfer back?

Has anybody had success with this approach before?