(e)
Termination of orders
At any time during which an order under this section applies, the Administrator may enter upon a public hearing respecting the availability of technology. Any order under this section shall be terminated if the Administrator determines on the record, after notice and public hearing, that the conditions upon which the order was based no longer exist. If the owner or operator of the smelter to which the order is issued demonstrates that prompt termination of such order would result in undue hardship, the termination shall become effective at the earliest practicable date on which such undue hardship would not result, but in no event later than the date required under subsection (c) of this section.