(a) If the Secretary determines that an amendment to a State plan is essential during the effective period of the plan, the State must make the amendment.

(b) A State must also amend a State plan if there is a significant and relevant change in the information or the assurances in the plan.

(c) If a State amends a State plan, to the extent consistent with applicable law, the State must use the same procedures as those it must use to prepare and submit a State plan, unless the Secretary prescribes different procedures for submitting amendments based on the characteristics and requirements of a particular State-administered formula grant program.