Oops! I missed resetting the cache array in the flush function in my last commit.
diff --git a/system/database/DB_active_rec.php b/system/database/DB_active_rec.php
index 5b118ce..d2d2632 100644
--- a/system/database/DB_active_rec.php
+++ b/system/database/DB_active_rec.php
@@ -1665,9 +1665,10 @@
'ar_cache_where' => array(),
'ar_cache_like' => array(),
'ar_cache_groupby' => array(),
- 'ar_cache_having' =>array(),
+ 'ar_cache_having' => array(),
'ar_cache_orderby' => array(),
- 'ar_cache_set' => array()
+ 'ar_cache_set' => array(),
+ 'ar_cache_exists' => array()
);
$this->_reset_run($ar_reset_items);