Practical perspective
Investigate a changed map result before explaining it
A changed observation is a starting point for investigation, not proof of a single cause.
Repeat the same observation
Compare the same query, sampled location and conditions. Record timing and visible differences so the comparison can be understood.
Check the business record
Review recent changes to the profile, website, services and availability. Distinguish an actual business change from a reporting or sampling change.
State the limits
A plausible explanation may still be unproven. Keep the observation, hypothesis and proposed next check separate instead of promising a ranking recovery.