As a test I created a field group that has 2 fields.
The first field is a taxonomy field and named taxonomy
The second field is a text field and named temp_field
I then created an acf/save_post filter with the priority set to 20, here is the filter
add_action('acf/save_post', 'test_tax_problem', 20);
function test_tax_problem($post_id) {
$tax = get_field('taxonomy', $post_id, false);
update_post_meta($post_id, 'temp_field', $tax);
}
What it does is simply get the new value from the taxonomy field after ACF and puts the value into the text field so I can see what value is being returned for the taxonomy field at this point.
Testing with different options I get these results
Save Terms = No, Load Terms = No : returns new terms
Save Terms = No, Load Terms = Yes : RETURNS OLD TERMS
Save Terms = Yes, Load Terms = No : returns new terms
Save Terms = Yes, Load Terms = Yes : returns new terms
These are exactly the results I would expect to get. Let me know if you do not understand why.
