It wont be an issue unless you have a problem paying extra for the difference
Again as far as I know , it will be the same deal as your first choice (mins, texts, web, etc...) but only the price will change. Then again there is also another rumour that orders that has been made before it has been removed from the web site will keep the same deals from different provider and there will be no difference on the deals-price, but the provider. Unless they dont send you an e-mail about the subject, there will be no problem and most likely they will inform you at one point, before or after the dispatch. Thank you.