Hi Kathleen,
Suhanth is mentioning that downloading the application from team server again would help in opening the app in version 9.11.0 again (assuming that the one committed in team server is 9.11.0).
You could download the app again using the following steps:
Import app package is different and used when you’ve already exported an app package and want to create an application out of the same package and upload to new team server or existing or have it stored locally on your machine. You can find more information here
Hope this helps!