(a) For affected sources that commenced construction or reconstruction on or before May 19, 2011, you must demonstrate compliance with the requirements of this subpart no later than January 6, 2014.

(b) For affected sources that commenced construction or reconstruction after May 19, 2011, you must demonstrate compliance with the requirements of this subpart by January 5, 2012 or upon startup of operations, whichever is later.

(c) Until the date specified in 63.546(a), secondary lead smelters that commenced construction or reconstruction on or before May 19, 2011, must continue to demonstrate compliance with the requirements of this subpart, codified in 40 CFR 63.541 through 40 CFR 63.550, that were in effect prior to the January 5, 2012, amendments. This means that secondary lead smelters that commenced construction or reconstruction on or before June 9, 1994, must continue to demonstrate compliance with existing source requirements of this subpart that were in effect prior to the January 5, 2012, amendments until the date specified in § 63.546(a). Secondary lead smelters that commenced construction or reconstruction after June 9, 1994, and on or before May 19, 2011, must continue to demonstrate compliance with new source requirements of this subpart that were in effect prior to the January 5, 2012, amendments until the date specified in § 63.546(a).