pub const SIGNATURE_REQUIRED_AFTER: u64 = 1_788_268_400;Expand description
2026-09-26: Unix seconds (2026-09-01T13:13:20Z). A record whose
recorded_at is below this and that has no .sig verifies as
Verified::Exempt; at or after it, a .sig is required.
signing_tests::no_committed_record_escapes_the_cutover_unsigned checks
every committed record against it.