If the update completes successfully, any unsaved data in Manuals you are creating or editing will not be lost.
However, if the update does not complete successfully, you may be logged out of the app.
Logging in again will complete the update, but any data that had not been saved before the Log Out will be discarded.
Related: "Data could not be loaded correctly. Please log in again to resolve this issue" is displayed
https://help.teachme.jp/hc/en-us/articles/14571088890521
We recommend saving the data on your device to the server before updating the app.
Related: Save Manual as Draft (Mobile App)
https://teachme.jp/8/manuals/41527928
Related: What is "Unsynced" in the mobile app?
https://help.teachme.jp/hc/en-us/articles/12095601263769