Someone else has suggested that a 9:16 file is effectively just 16:9 on its side counterclockwise, so if you shoot vertical and edit with a stiff neck, a 16:9 sideways file will work?
I’m not sure that First has enough similarities with MC for it to be described as a trainer.
I guess you do get an insight into the things that have been driving us nuts for years, namely Avid’s super fussiness about hardware, codecs and drivers and it’s preference for end customers to do the beta testing on every new release.