Woocommerce Local Pick Up Plus Only Show One Pickup Location based on certain condition

I am using the Local Pickup Plus Plugin for Woocmmerce. What I want to do is to have multiple pick up locations in the back end, but only allow to show one in the checkout process, so the customer is no able to choose anymore, but will be presented with the correct one for him.

The correct one should be set via its ID and chosen based on a condition I set beforehand via jQuery.

What I cannot figure out now, is how to modify the dropdown table on the checkout page as there is no real documentation to the plugin.

Here is a snippet I've found on Github, which does not really seem to have any effect though.

function wc_local_pickup_plus_remove_pickup_location() {

$methods = WC()->shipping->load_shipping_methods();

if ( isset( $methods['local_pickup_plus'] ) ) {
    remove_action( 'woocommerce_after_template_part', array(  $methods['local_pickup_plus'], 'review_order_shipping_pickup_location' ), 10, 4 );
add_action( 'wc_shipping_local_pickup_plus_init', 'wc_local_pickup_plus_remove_pickup_location' );

I would welcome any help! Thanks a lot already.