Currently there is no UTC-anchored date filtering on the stable Contact Search API.
ETL Tool Fivetran is unable to provide accurate Intercom Contact data due to this gap.
There is no way for the Stable API to pull accurate Intercom data even though accurate data exists at the individual contact id level.
Pulling contacts one by one is unusable for managing a large amount of data. Large amounts of data must be pulled in batch, but due to lacking UTC-anchoring, data is pulled based on local timezone and results in gaps.
Having this feature in the Preview API is not helpful until it gets added to the Stable API because the Preview API is not a stable standard without guarantees of no bugs due to new features.