I've noticed - and reproduced successfully a few times - an issue where pictures do not save to a note after capture (current app version is 8.7.0):
Hit Add > Camera (Or Camera icon in note to add images) to open image capture screen
Take picture of document in portrait or landscape mode
While picture is saving, rotate phone to other orientation (so like from portrait to landscape)
Take another picture
Hit save icon
Note appears blank
If you let the images save before rotating the phone to a different orientation, it works. But if you're a little too quick or your phone accidentally switches orientation, all captured images are just gone and the note is blank.
I no longer have a Premium account so can't submit this to the developers, so thought I'd share here to see if anyone is able to submit this bug, has recreated it and it's already been submitted, or knows a solid fix to this.