Big question
How fixed should a plan be when automated systems re-decide its split after signing?
The position
Fix the total, the guardrails and the reallocation triggers, and treat the channel split as an opening position. Write the triggers before the campaign starts, because nothing varies on purpose afterwards.
Why it is live
The plan's split becomes an opening position once an automated system can move money between lines, and no field on the plan records what moved or when. The 2026 CMO Survey reported strong economic pressure and a shift toward short-term impact, so plans are now being reopened by conditions as well as by machines.
The case for a loose plan
InferredConditions and auctions both move faster than a planning cycle, and a rigid split is re-cut by the buying system regardless of what the document says.
The case against
UnknowableNothing varies on purpose inside an automated split, so there is nothing to hold back and compare, and a plan that fixes nothing cannot be audited afterwards.
Where the weight sits
For flexibility with pre-agreed triggers, and firmly against flexibility without them. The distinction between those two is the entire answer.
What would change this
A holding company or a large planning product publishing a field schema showing what a plan records when an automated system moves money between its lines.
Where this is taught
Strategy and Planning
Sources
- The CMO Survey, 31 Mar 2026secondary
- IAB 2026 outlook study, 28 Jan 2026secondary