Drop in organic traffic that aligns with the date of an announced update is the primary signal. Use Search Console's date-range comparison and segment by query type. A sudden drop on commercial-intent queries usually points to a quality issue; a drop on informational queries often reflects AI Overview cannibalization.
Hundreds of small changes per year, plus 4-6 announced 'Core Updates' annually. Most small changes are imperceptible.
No. Wait until the update finishes rolling out (usually 2 weeks), then assess and respond.
Updates often reweight signals; sites that were marginal before drop. Recovery comes from genuinely improving the marginal signals.
Almost never. Google does not roll back; they iterate forward. Treat each update as the new baseline.