Thanks so much for the reply. I was making this way more complicated than it needed to be. The Taxonomy Field:
$selected = get_field('selected_tags');
was already returning an array of IDs making my variable:
$selectags = implode(",",$selected);
completely unnecessary. Working code is below. Hopefully it’ll save somebody else some time & trouble.
<?php
$postnumber = get_field('number_of_posts');
//custom field for posts per page
$selected = get_field('selected_tags');
// ACF Taxonomy Field (Return Value = Term ID)
?>
<?php $args = array(
'posts_per_page' => $postnumber,
'orderby' => 'post_date',
'order' => 'ASC',
'post_type' => 'post',
'post_status' => 'publish',
'tag__in' => $selected
); ?>
<?php query_posts($args); if (have_posts()) :
while (have_posts()) : the_post(); ?>
<h2><?php the_title(); ?></h2>
<p><?php the_excerpt(); ?></p>
<a href="<?php the_permalink() ?>">read the post</a>
<p><?php the_tags('Tags: ', ', ', ''); ?></p>
<?php endwhile; endif; ?>
<?php wp_reset_query(); ?>
