Export Audio - Mix Scence, is this new?

I noticed this when I exported audio and saw the screen jumped around a bit and the exported mix doesn't sounded right.  Then I saw that it defaulted (not consistent though) to a Mix Scene, and I've always used 'entire mix'.  Strange behavior, is there a way to set the default or have it sticks to whatever you have set to prior (the good old way)?

Did a little more digging and see that if you have any mix scene saved, the option to export the mix scene will appear.  After rebooting the behavior is consistent, i.e., it will remember your last selection.