Add backup note

README.md

@@ -100,6 +100,7 @@ If you're fortunate, this has in fact worked. At this point, you can re-enable
 the readiness/liveness checks, push this with `helm upgrade` as per above, and
 cross your fingers that you've saved the day.
 
-This process has in fact worked once before, so it's probably fine.
+This process has in fact worked once before, so it's probably fine. For backup
+caveats, note https://gitlab.com/charts/charts.gitlab.io/issues/96
 
 Good luck!