I have tried to do some debugging and you are correct. The value is set but when rendering the field to show already selected posts ACF calls get_psots() with the following arguments
Array
(
[posts_per_page] => -1
[post_type] => Array
(
[0] => tribe_events
)
[post_status] => any
[update_post_meta_cache] =>
[update_post_term_cache] =>
[post__in] => Array
(
[0] => 6092
)
)
and this returns no results. The only conclusion at this point that I can come to is that there is something in the events plugin that is interfering with this query.
