diff --git a/FAQ.md b/FAQ.md
index d5a04e97b0..fb28454281 100644
--- a/FAQ.md
+++ b/FAQ.md
@@ -1335,6 +1335,13 @@ consider switching to a modern provider which supports push messages (IMAP IDLE)
 If your device has an [AMOLED](https://en.wikipedia.org/wiki/AMOLED) screen,
 you can save battery usage while viewing messages by switching to the black theme.
 
+By default auto optimize in the receive settings is enabled,
+which will switch an account to periodically checking for new messages when the email server:
+
+* Says '*Still here*' within 3 minutes
+* The email server does not support push messages
+* The keep-alive interval is lower than 12 minutes
+
 <br />
 
 <a name="faq40"></a>