No. We do not store any files or have any servers. If you delete the app, the files inside are gone and could only be recovered if you use iCloud Backup on your device.
If your files are on an old device and you need to export or transfer them: https://float.support/article/9000205854
We also have no user accounts and store no identifiable information.
If you have previously used the premium option to manually backup files to your icloud, there is no longer a need to manually restore them. The app will automatically check for any files in the cloud every time it opens. As long as your phone is signed into the same Apple account that you backed up the files with, it will be able to retrieve your files. Note that if you deleted your iCloud files, or stopped paying for iCloud storage, this may prevent the files from being restored.