I believe I’ve found an actually really simple solution for this – set $value to an array of your default values inside the acf/load_value hook.
add_filter('acf/load_value/key=field_54aa5b3b008b0', 'afc_load_my_repeater_value', 10, 3);
function afc_load_my_repeater_value($value, $post_id, $field) {
if ($post_id === false) {
$value = array();
$value[] = array(
field_54aa5beb008b1 => 'Hours',
field_54aa5c25008b2 => 1
);
$value[] = array(
field_54aa5beb008b1 => 'Minutes'
);
$value[] = array(
field_54aa5beb008b1 => 'Seconds'
);
}
return $value;
}
I have more details on this post.
