Most probably don't use it. But it's good practice to do so.
Yes, being locked out as a result is a pain. Lots don't understand that can happen if you change or lose phone. Cb doesn't as far as I know provide for an alternate method to verify in such cases. Which they really should.
Once back up, take a look at Authy to do the authorization. You can set it up on multiple devices (phone, tablet, computer). If you don't have your phone you'll have other backup device that you can use to gain access.