I've been trying to create a file that combines 608 and 708 captions in Premiere Pro CC 2017. When I create the file using .scc captions it seems I can only make it in either 608 or 708. When I create the file using .mcc captions, I can see both the 608 and 708 captions when I play it back on my timeline but when I send it to our server as an .mxf op1a file the server only sees the 708 captions.
What am I missing? Do I need to stack the captions when using a .scc file?