Yep. Look into showflat.tmpl and showthreaded.tmpl files located in your templates folder.
Close to the end on both files you will see this:
<br />$r {$ubbt_lang['C_ONLINE2']} $a {$ubbt_lang['C_ONLINE4']} <br /><br /><br /><br />
Remove it and that will exclude this information.
However instead of deleting the lines, I would suggest you do something like this:
<br />UBBTPRINT;<br />// 20030201 - Removed by dreamer - Old Start<br />/*<br />$r {$ubbt_lang['C_ONLINE2']} $a {$ubbt_lang['C_ONLINE4']} <br /><br /><br /><br />*/<br />// 20030201 - Removed by dreamer - Old End<br />echo <<<UBBTPRINT<br />
The above will comment the lines rather than you hitting the delete key and later on try to find where this information went should you need it in the future.
Warm regards
Nikos