.woolentor-backorder-fields p{
    display: none;
}
.wl_manage_stock--no.wl_stock_status--onbackorder p,
.wl_manage_stock--yes.wl_allow_backorder--yes p,
.wl_manage_stock--yes.wl_allow_backorder--notify p{
    display: block;
}
#_woolentor_backorder_availability_date{
    float: left;
}