Standards under
section 7411 of this title and this section applicable to solid waste incineration units with capacity greater than 250 tons per day combusting municipal waste shall be promulgated not later than 12 months after
November 15, 1990. Nothing in this subparagraph shall alter any schedule for the promulgation of standards applicable to such units under
section 7411 of this title pursuant to any settlement and consent decree entered by the Administrator before
November 15, 1990:
Provided, That, such standards are subsequently modified pursuant to the schedule established in this subparagraph to include each of the requirements of this section.