diff --git a/docs/html/config_channels.html b/docs/html/config_channels.html
index 5062c39e..7ad8f9ed 100644
--- a/docs/html/config_channels.html
+++ b/docs/html/config_channels.html
@@ -41,7 +41,8 @@
       that should be used to update this channels EPG info.
       By default Tvheadend tries to match the name itself, but sometimes
       it might not match correctly in which case you can do the mapping
-      manually.
+      manually. When using XMLTV, a newly-mapped channel will not appear
+      in the EPG until the next run of the grabber, or service restart.
       <p>
       Over the air (OTA) sources do NOT need to be mapped in this way, the
       linking is implicitly tied since they are all part of the DVB system.