Deactivating stops the scheduled work and leaves your settings, your subscriber list and your counts alone.
Deleting removes them only if you ticked Delete all data on uninstall under Settings, which is off by default. On a network the tick is per site, and only the sites that asked are cleared.
The page shown during WordPress updates, wp-content/maintenance.php, goes on deactivating and on deleting either way. If you remove the plugin's folder over FTP instead, delete that file by hand too.
Still stuck? Ask the developers who wrote it. We aim to reply within one business day.
