While you can “Edit” the Baseline while there are Open Actions for it, the ACTIONS themselves will NOT be impacted by it.
You have to stop them and re-Deploy the Actions. Actions (from Baselines, Fixlets, or Tasks) actually have COPIES of the source content. This is done to prevent inadvertent behavior when someone edit’s the source Content (be it YOU or BigFix.com updating their content).
It is the same when it comes to Fixlets/Tasks and Baselines. The Fixlet/Task content is COPIED into the Baseline and modifications of the original Fixlet/Task will not impact what is in the Baseline. You must SYNCHRONIZE the components, either manually or using the Wizard.