Short answer
Run a new ad set for at least a full week before you judge it, and longer if it is still learning. Meta says ad sets usually leave the learning phase after about 50 results in the week after their last significant edit.
Why a week is the floor
- Meta paces daily budgets across the calendar week, so single days swing up and down.
- During learning, Meta says results are not necessarily a guide to future performance.
- Editing an ad set during learning resets it and delays optimisation.
When to change or stop an ad
- It has left learning and its cost per result stays above target for a full week.
- Results drop as the same people see it again. Meta suggests refreshing creative a few times a month for Advantage+ app campaigns.
- Avoid pausing an ad set for 7 days or longer if you plan to restart it, because it re-enters learning when unpaused.
In practice
There is no maximum. A strong ad can run for months. Keep winners live and launch new creatives in batches, because adding a new ad to an ad set counts as a significant edit. Review performance weekly on cost per install or in-app event and on cohort revenue.
See how we manage Meta campaigns for apps on our Facebook ads agency page.
Sources checked 4 October 2026
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