You can decide to switch or replace the dataset during or after the creation of your recipe. Let's say you created the recipe using last month's sales data. Once the next month's sales data is ready, you can just swap out the dataset in your flow with the new dataset and run the job to get the wrangled data as an output.
Source Swap
In the flow view, right click on the currently imported dataset that is used in your recipe. Select Replace.
Select the new source from your resource library.
You can also click on Import Datasets to import a new dataset if it does not already exist in your library.
Select the dataset and click Replace.
Your recipe is now using the selected dataset as its source.
Note-
You can swap back to your original dataset
If there are differences between the schemas of the source and the new source, you may have to update your recipe.
More Info
To learn more about changing your datasets, read this detailed documentation guide.