If someone would have presented me the designs above I would have guessed that the previous design was the new one.
Here is why:
On payment method screen, the cvv input has a clear connection to the payment method 'credit card'. This is crucial since not everybody might understand what the cvv is if it is not somehow in connection with the credit card.
There is no yes or no to this question. It depends largely on what your site should do and what your users need. Here are some questions you should investigate:
What informations do your users need?
What is the main device your users use your site (on b2b sites it could (but doesn't have to be) probably be desktop instead of mobile)?
How important is it to ...