Normative systems accommodate temporary norms of several types, which can also be modied in dierent, and codied ways. In this paper we address the problem of modifying temporary norms that are represented by means of the combination of two known formalisms in the current literature. The framework evolves from a known one, which provides a system of norms at two distinct layers, and represents changes at the two layers as means to provide room for the codied change types. This results in four novel operators that anticipate and extend norms in two dierent combined ways, by preserving or not the eects of the norms in the period of time generated by the temporal modications. We study these new operators and show how they relate to the operators of annulment and abrogation analysed elsewhere.