You've added a block to a preset and realize one of its parameter values is incorrect. Do you have to remove the block and start over? No, you can adjust the block parameter values to your liking and then update that specific block within the preset. There are several ways to do this, as outlined below.
In the Processing Workspace toolbar, click Presets to open the All Presets dialog box.
tip: If you want to update a block in multiple presets, simply leave the Preset References dialog box open, make the necessary changes to the block, and click the appropriate Update button. Repeat this process for each preset. This is a handy way to focus your attention on a single block, thinking about its configuration for each of its presets.