@cathyf31, the black box restricting more than two years use was lifted int 2021. Guidelines remain because there was no rigorous testing of Tymlos for longer than two years. Doctors are not required to follow guidelines, as they are just general guides. Many drugs are prescribed off label. Tymlos is becoming more frequently prescribed in this fashion.
Lots of literature remains on the net long after it was initially thought to be true. University websites are particularly remiss at updating and they often don't contain source listing or dates of publication.

@cathyf31
I did research it after your message. I don’t know how to show you what I found, but Thankfully my doctor is accurate.