Temporal Shunt

5th-Level Transmutation
Casting Time: 1 reaction, taken when a creature you can see makes an attack roll or starts to cast a spell
Range: 120 feet
Components: VS
Duration: 1 round

As in Explorer's Guide to Wildemount with the following change:

At Higher Levels. When you cast this spell using a spell slot of 6th level or higher, the duration increases by 1 round for each slot level above 5th.

Source: EGW 189

Changelog

Altered upcasting option.