This is the most likely reason for that app to get a warning like that. They have made a lot of changes to their 3rd party app security model that would require

This is the most likely reason for that app to get a warning like that. They have made a lot of changes to their 3rd party app security model that would require apps to be updated, even if they were well-behaved under the old model. It's unfortunate that could not have been done with forward compatibility.