01
Every policy in the export you send is reconciled, on a date range you can name.
A review that cannot say which enrollments it covered is not a review. The question "has this client left my book" is only answerable inside a stated date range, because comparing an all-time ledger against a date-sliced export makes every older client look lost.
Instrumented
The audit computes the export's own date range and states it on every subject line. Absence is only treated as a loss inside that range. Clients whose dates cannot be read are skipped, not flagged. If the date column disappears upstream, the run stops rather than letting the range silently widen to everything.
