Controls whether or not to send membership level expiration warning emails. Passes the boolean true or false and the user ID.

apply_filters("pmpro_send_expiration_warning_email", true, int $e->user_id);

Parameters

bool (true)

$e->user_id

int

Source

File: https://github.com/strangerstudios/paid-memberships-pro/blob/master/scheduled/crons.php