Bug in 2.1.0 with BackWPup

When updating to the latest version when BackWPup is installed, there is a critical error:

/home/domain.com/public_html/wp-content/plugins/salt-shaker/vendor/freemius/wordpress-sdk/require.php. Error message: Uncaught Error: Failed opening required '/domain.com/public_html/wp-content/plugins/salt-shaker/vendor/freemius/wordpress-sdk/includes/class-fs-hook-snapshot.php' (include_path='/home/domain.com/public_html/wp-content/plugins/backwpup/vendor/pear/archive_tar:/home/domain.com/public_html/wp-content/plugins/backwpup/vendor/pear/console_getopt:/home/domain.com/public_html/wp-content/plugins/backwpup/vendor/pear/pear-core-minimal/src:/home/domain.com/public_html/wp-content/plugins/backwpup/vendor/pear/pear_exception:.:') in /home/domain.com/public_html/wp-content/plugins/salt-shaker/vendor/freemius/wordpress-sdk/require.php:61Stack trace:#0 /home/domain.com/public_html/wp-content/plugins/salt-shaker/vendor/freemius/wordpress-sdk/start.php(584): require_once()#1 /home/domain.com/public_html/wp-content/plugins/salt-shaker/vendor/composer/autoload_real.php(41): require('...')#2 /home/domain.com/public_html/wp-content/plugins/salt-shaker/vendor/composer/autoload_real.php(45): {closure:ComposerAutoloaderInitd81092cc23a0cb0a8b7d8b87af5e6708::getLoader():37}()#3 /home/domain.com/public_html/wp-content/plugins/salt-shaker/vendor/autoload.php(25): ComposerAutoloaderInitd81092cc23a0cb0a8b7d8b87af5e6708::getLoader()#4 /home/domain.com/public_html/wp-content/plugins/salt-shaker/salt-shaker.php(34): require_once('...')#5 /home/domain.com/public_html/wp-settings.php(545): include_once('...')#6 /home/domain.com/public_html/wp-config.php(119): require_once('...')#7 /home/domain.com/public_html/wp-content/plugins/salt-shaker/vendor/freemius/wordpress-sdk/require.php. Error message: Uncaught Error: Failed opening required '/domain.com/public_html/wp-content/plugins/salt-shaker/vendor/freemius/wordpress-sdk/includes/class-fs-hook-snapshot.php' (include_path='/home/domain.com/public_html/wp-content/plugins/backwpup/vendor/pear/archive_tar:/home/domain.com/public_html/wp-content/plugins/backwpup/vendor/pear/console_getopt:/home/domain.com/public_html/wp-content/plugins/backwpup/vendor/pear/pear-core-minimal/src:/home/domain.com/public_html/wp-content/plugins/backwpup/vendor/pear/pear_exception:.:') in /home/domain.com/public_html/wp-content/plugins/salt-shaker/vendor/freemius/wordpress-sdk/require.php:61Stack trace:#0 /home/domain.com/public_html/wp-content/plugins/salt-shaker/vendor/freemius/wordpress-sdk/start.php(584): require_once()#1 /home/domain.com/public_html/wp-content/plugins/salt-shaker/vendor/composer/autoload_real.php(41): require('...')#2 /home/domain.com/public_html/wp-content/plugins/salt-shaker/vendor/composer/autoload_real.php(45): {closure:ComposerAutoloaderInitd81092cc23a0cb0a8b7d8b87af5e6708::getLoader():37}()#3 /home/domain.com/public_html/wp-content/plugins/salt-shaker/vendor/autoload.php(25): ComposerAutoloaderInitd81092cc23a0cb0a8b7d8b87af5e6708::getLoader()#4 /home/domain.com/public_html/wp-content/plugins/salt-shaker/salt-shaker.php(34): require_once('...')#5 /home/domain.com/public_html/wp-settings.php(545): include_once('...')#6 /home/domain.com/public_html/wp-config.php(119): require_once('...')#7 /home/domain.com/public_html/wp-load.php(50): require_once('...')#8 /home/domain.com/public_html/wp-admin/admin.php(35): require_once('...')#9 /home/domain.com/public_html/wp-admin/plugins.php(10): require_once('...')#10 {main} thrown/public_html/wp-load.php(50): require_once('...')#8 /home/domain.com/public_html/wp-admin/admin.php(35): require_once('...')#9 /home/domain.com/public_html/wp-admin/plugins.php(10): require_once('...')#10 {main} thrown