I may have found the actual problem.

In the /storage/ directory there are a number of bx_... directories.   All of them were owned by www-data except bx_timeline_videos_processed which was owned by root.   I did a  chown -R www-data:www-data bx_timeline_videos_processed and now posts from yesterday are showing up with working video's.

I have to check with other users to see if their videos are now working as well.

Keep your fingers crossed.