CA Fam Code Section 5700.612

If a child-support order issued by a tribunal of this state is modified by a tribunal of another state which assumed jurisdiction pursuant to the Uniform Interstate Family Support Act, a tribunal of this state:

(1)

may enforce its order that was modified only as to arrears and interest accruing before the modification;

(2)

may provide appropriate relief for violations of its order which occurred before the effective date of the modification; and

(3)

shall recognize the modifying order of the other state, upon registration, for the purpose of enforcement.