Update: I was at 10 devices. I signed out of one, but nothing at all changed. I signed out of 2 more, and now my primary mobile number, when used to confirm a sandbox account, does NOT say: Could not connect to iCloud - This phone number has been used too many times. Choose a different number. ...now it says... Too Many Codes Sent - You have sent too many codes to this phone number. Please enter the last code you received, enter another phone number or try again later. (Of course I never received any codes at all. From either number.) It is then waiting for me to enter a code. (Regardless of which number I try.) I have no codes for either. I'll try again tomorrow.
Topic:
App & System Services
SubTopic:
StoreKit