Adding a second phone number to receive a multi-authentication code

I am traveling abroad and my husband is staying locally.  We would both like to access box.com but the authentication process provides a code ONLY to his cell phone.  Since there will be 15 hours time difference between us, it would not be convenient to phone him for the code every time I have to log on.  Does Box.com allow for two phone numbers as options where to send the multi-authentication code?  Thanks for your help!