A quick primer
It helps to understand the underlying mechanics here: replacing text inside an existing RSA is an edit to a live ad, not the creation of a new one. The ad's overall accumulated stats (total clicks, conversions, history as a single Ad ID) don't reset. But every individual new asset (a new headline or description swapped in) starts from zero — it has no history and has to build its own data from scratch, regardless of how old the ad itself is. That's exactly why "how often to refresh" comes down not to whether you can refresh at all, but to how many assets you swap at once and how often, so you're not wiping out the statistical base wholesale.
The practical industry recommendation is not to replace all headlines at once, but to refresh 2–3 at a time, preserving most of the accumulated data while the new copy gets tested, rather than rebuilding the ad from scratch. A second practical benchmark is the minimum waiting period before evaluating new assets: allow at least 2–4 weeks to accumulate enough impressions for a reliable rating, since replacing assets too quickly doesn't give the system time to learn the new variant. Google's own guidance shifts the emphasis from "how often to refresh" to "how saturated the asset pool is": most of Google's recommendations emphasize maximizing asset diversity as a more significant factor than refresh cadence itself — meaning regular updates don't substitute for having a sufficiently broad and diverse text pool from the start.
What to check before you touch anything
- Which specific assets you plan to replace — genuinely low-performing ones (a Low rating, see question 4.2), or ones picked arbitrarily without data support.
- How many impressions have accumulated on the assets you're about to replace — if a "Low" rating is based on a small impression count, replacing it may be premature.
- How long it's been since this group's assets were last updated — if it's been a long time (several months or more) at a stable, competitive market, alongside a gradual CTR decline, that leans toward genuine copy fatigue.
- Whether you're about to replace more than half the pool in one pass — that's effectively a full rebuild rather than a targeted refresh, and the ad's overall statistical base becomes less informative for a transition period.
- Whether the ad group has enough traffic for new assets to accumulate a statistically meaningful volume of impressions within a reasonable window (weeks, not months).
Possible approaches
- The standard approach: rotate in a targeted way — replace the 2–3 weakest-performing headlines (or descriptions) at a time, leaving the bulk of the pool untouched, and repeat the cycle as new data accumulates.
- After a replacement, wait at least 2–4 weeks before touching the same position again, giving new assets a real chance to build data rather than judging them on the first few days.
- If the whole pool is genuinely outdated (stale promos, irrelevant USPs) and hasn't been touched in a long time — a larger rebuild can be justified, but be aware that part of the ad's accumulated statistical base will be less informative for a while until the new assets build data.
- If the ad group is low-frequency — touch the copy less often overall: on low traffic, every replacement takes disproportionately long to accumulate meaningful data, so frequent edits do more harm than good there.
- A scheduled audit (say, quarterly) with targeted replacement of only data-confirmed underperformers is a more sustainable practice than reactive edits based on a feeling that "the copy is stale," without numbers to back it up.