I’m using the pre_get_posts filter (shown below) to sort my homepage post loop by a custom metavalue.

function custom_loop_for_loggedin_users( $query ) {
    if ( is_user_logged_in() && $query->is_home() && $query->is_main_query() && ! is_admin() ) {
	    $user_cat_ids = get_category_ids_of_bp_groups( bp_loggedin_user_id() );
	    $tax_query = array(
	        array(
	            'taxonomy' => 'category',
	            'field'    => 'term_id',
	            'terms'    => $user_cat_ids,
	        ),
	    );
	    $query->set( 'tax_query', $tax_query );
	    $query->set( 'meta_key', 'hot_rank_score_cached' );	    
	    $query->set( 'orderby', array('hot_rank_score_cached' => 'DESC', 'date' => 'DESC'));
    }
}
add_action('pre_get_posts','custom_loop_for_loggedin_users');

But I’m also using the Blog Categories for Groups plugin, and would like to apply a similar custom sort to the group blog posts.

I’ve been digging through your plugin to see how you query those posts, but I can’t figure it out.

Am I able to apply a custom sort to the group blog posts? Can you point me in the right direction?

Was hoping to use something like pre_get_posts or WP_Query if possible.