'category__and' with multiple input

Hi,
I am wondering if I am able to get multiple input into ‘category__and’ (or ‘category’) argument separated by OR (or AND in ‘category’ case).

I have something like this:

$args = array(
	      'posts_per_page'  => '10',
	      'numberposts'     => '',
	      'offset'          => 0,
              'category__and'   => $category_array,
	      'orderby'         => 'post_date',
	      'order'           => 'DESC',
	      'post_type'       => 'post',
	      'post_status'     => 'publish',
	      'suppress_filters' => false );   

      $myposts2 = new WP_Query( $args );

And it works great. But yesterady, the task changed and user now can choose more options in one filter category. So I need change query to something like this:

$args = array(
	      'posts_per_page'  => '10',
	      'numberposts'     => '',
	      'offset'          => 0,
              'category__and'   => <strong>$category_array_1 OR $category_array_2 OR $category_array_3</strong>,
	      'orderby'         => 'post_date',
	      'order'           => 'DESC',
	      'post_type'       => 'post',
	      'post_status'     => 'publish',
	      'suppress_filters' => false );   

      $myposts2 = new WP_Query( $args );

I can make those combination earlier in the code, but, I cant get this OR thing working and I can’t find any solution neither (maybe I am just blind). I am usualy capable to do my homewrok properly, but searchin for “OR” is kind of tricky…thanks for any help ??

EDIT: I can probably create a workaround with multiple queries, but I’d like to have it in one query.