Thank you, Jeff, for the answer.
“This only happens for the first clip. After the first clip is on the timeline, FCP assumes that ALL THE CLIPS will be that format and does whatever magic necessary to let other formats work.”
So if I open a new project, will Timeline continue to use “that format” as its key format and work from there? Or does it start all over and work with the format of the “new first clip” in the new project? Thank you.