In the LivePlan forecast sections that have a “varying amounts” option, we’ve added fill-right functionality. Each field in the grid has the fill-right option, except for the very last one.
To use this feature, click in a field that contains the value you want to copy across. Next, click the three blue dots below that field, and then click the Apply button. The value from the field you selected will be copied into all of the fields to the right of the selected cell. 
Click I'm Done to save your changes.