A created campaign is not locked. You can change its dates, locations, formats, POIs, audiences and media owners at any time.
Edits work differently from building a draft, and the difference matters: your changes are gathered together and you review the full consequence before anything is applied.
Making Changes
Open the campaign and go to Manage → Edit.
The planner opens, working the same way it did when you built the campaign.
Change whatever you need across the steps.
Nothing has changed on the live campaign yet. You are working on a set of pending edits, which is why you can take your time and revise across several steps before committing.
Reviewing What Will Change
When you apply your edits, a Review Campaign Changes screen appears first. It breaks the changes down by the part of the campaign affected — dates, locations, formats, POIs, audiences, media owners, attachments — so you can see precisely what you altered.
It also shows a Unit Summary: how many units match your revised criteria, and how many will be removed as a result. Removed units are listed individually with their Face IDs.
Read the removal count before continuing. Narrowing dates or formats can drop units you had already secured, and this screen is where you find that out rather than afterwards.
Keeping The Units You Marked Up
The review screen has a checkbox worth knowing about:
"Keep favorited, recommended, and in cart units."
Tick it and units you have shortlisted or moved towards booking survive the edit, even if they no longer match your revised criteria. This protects your work.
*Note: If you have spent time building a shortlist, tick this box. Recovering favorites lost to an edit means finding each unit again by hand.
Applying Your Changes
Click Update Campaign to apply. The edits are written to the live campaign together, and your pending set is cleared.
If you decide against the changes, close the review screen without confirming and the campaign is untouched.
Changing Dates On A Live Campaign
Dates are the most consequential thing to edit, because availability is tied to them. Moving a flight can invalidate holds you already have, and the review screen will show those units as being removed.
If a date change is significant, it is often better to talk to your media owners first and then make the edit, so you are not releasing inventory you would struggle to get back.