This is something recent and I do not know when this was changed. As I said, at one time get_field() on the front of the site would only return published posts and/or any post the the current visitor was allowed to see. Now both post object and relationship fields call the function acf_get_psots() and this function forces
'post_status' => 'any' and there are no filter hooks available in ACF to modify this.
Currently there are two choices
Beyond this the only advice I can give to to contact the developers. It appears that this function is used on both front and back end queries now and without adding them adding a filter to alter this in the format_value function for the field I don’t see any other way around this issue at this time.
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