Greetings from Amazon Seller Support,
Thank you for contacting us.
I have reviewed your email and understand that you are going to get new credit card number from bank but that would take 2-3 days and you want to know how it would affect on your account. Let me address your issue.
Please be informed that, this can be affect those orders that you need to fulfill within 2-3 days. As late shipping and late response to buyer's email could be affect your metrics.
I would like to give alternatives to handle this issue, so, that will save you from any affect on your metrics and performance.
***Please be informed that you can login from your Amazon.ca account and put your account on vacation. So, your all listing will be inactive till the time you update your credit card and then you can active your listing.
Please be informed that, this would be helpful for you in case you do not have any pending order in your selling account.
***If you have any pending order, so, in this case you can use other credit card of any family member or friend till the time you will get your.
Please be informed that, that credit card can be charge if you have any negative balance in your selling account.