I just used it on my iPhone 6 with iOS 10.2 a couple of days ago. Remember that the option only exists when you try to use it on an iMessage that has been sent (or is in the process of being sent), but hasn't been delivered yet.
I just used it on my iPhone 6 with iOS 10.2 a couple of days ago. Remember that the option only exists when you try to use it on an iMessage that has been sent (or is in the process of being sent), but hasn't been delivered yet.
The send button won't really do anything. It's basically there once you sent an iMessage before it is delivered--you can tap and hold on the iMessage that hasn't been delivered yet and that should give you the option to send it as SMS.