$per = $periods - 1;
$date = $date_ = get_post('date_');
$freq = get_post('freq');
+ if ($freq == 3 || $freq == 4) {
+ $date_ = begin_month($date_); // avoid skip on shorter months
+ $date = end_month($date_); // avoid skip on shorter months
+ }
$lastdate = ($freq == 1 ? add_days($date_, 7*$per)
: ($freq == 2 ? add_days($date_, 14*$per)
: ($freq == 3 ? add_months($date_, $per)