When created and residing in the originating Library, a FB album behaves much like any other album. Edits to the Versions that were placed in the Album, wherever they occur, will be reflected in the FB album, and can be synced to FB. Where albums are not originated in the Library, but instead are downloaded from FB, edits and other operations are not possible with those images.
If you lose your albums in the originating Library because of removing the web account entry while in the Library, the albums will NOT later reconnect to the originals, but will stay the same as those merely downloaded from FB. It is a complicated and fragile relationship between the Library and FB, and care must be exercised to not change the relationship.
Web account info resides in the com.apple.aperture.plist file, but whether the web account is Enabled or Disabled resides in an individual Library. Thus care should be taken to not be in the Library where FB accounts are administered when either removing web accounts or purging the com.apple.aperture.plist file to solve problems you are having in Aperture.