Executing view twice with different filters returns same results
The second argument to views_get_view is $reset:


  If TRUE, reset this entry in the load cache.


So second time around you just need to pass that:

$view = views_get_view('my_view');
$view-&gt;set_display('default');

...

$view = views_get_view('my_view', TRUE);


That will reset the static cache and the data will be fresh.