Update NIE spec's "Updated on $DATE" line
diff --git a/doc/spec/nie-spec.md b/doc/spec/nie-spec.md
index 7fb7c23..ffce34b 100644
--- a/doc/spec/nie-spec.md
+++ b/doc/spec/nie-spec.md
@@ -1,6 +1,6 @@
# Naïve Image Formats: NIE, NII, NIA
-Status: Draft (as of December 2020). There is no compatibility guarantee yet.
+Status: Draft (as of November 2021). There is no compatibility guarantee yet.
A companion document has further discussion of [NIE related
work](/doc/spec/nie-related-work.md).
@@ -370,4 +370,4 @@
---
-Updated on December 2020.
+Updated on November 2021.
