When creating a campaign, you have the option to select the audience as either Dynamic or as Static. When choosing Static, the audience you have selected for the campaign will be sent to only those in the audience at the time of launch. Changes to the audience will not cause any additional participants to be added to the campaign. However, when choosing Dynamic, if a participant is added to the audience associated with that campaign, they will also be added to the campaign starting on Day 1 of the timeline.
⛔ Please note: Removing a participant from an audience associated with a campaign will not remove them from the campaign itself.
Learn more about Audiences: