I don't remember reading about any changes to the payment system, although they might have changed some things, so realistically the best thing you can do is just try it? I've personally not had any problems, but your post says about having the problem when attaching the credit card so if you tried now you wouldn't be charged until your subscription is actually due anyway.

If you still can't get the card to work, you could do it with Crysta and I believe there are multiple methods to top up the Crysta, including PayPal (so you could essentially use your card with PayPal to get Crysta to pay your subscription). A bit long winded, but should work if you can't do it directly.