fly image update --image does not work

[punkpeye]

$ fly image update --app X --image X
No changes to apply

This just says "No changes to apply"

[punkpeye]

Looks like it doesn't even matter what is provided as --image.

The argument is just ignored.

[punkpeye]

@davissp14 any input here?

[davissp14]

What does fly image show indicate?