The introductory text to Appendix U suggests that the linked change summary document contains more detail about changes between TTML1 and TTML2, but this is out of date since the document now only contains changes between TTML2 1st Edition and TTML2 2nd Edition.
The introductory text to Appendix U suggests that the linked change summary document contains more detail about changes between TTML1 and TTML2, but this is out of date since the document now only contains changes between TTML2 1st Edition and TTML2 2nd Edition.