I moved a snapshot from NY3 to NY1 using the "Snapshot Availability" dropdown.
This dropdown shows selected regions as disabled.
This is an ambiguous user interface and misleading to users. As the help text says "Select the regions that you would like your snapshot to be available in", but the interface shows those regions as disabled.
This is an incorrect usage of the disabled state. A region that a snapshot is available for should be shown with a check mark, and a disabled region should mean that the snapshot can not be copied to that region.
A list of regions with check marks is a more appropriate interface.