In section 3.2.2.3.2 (Session Expiry Interval), the wording is:

If the Session Expiry Interval is absent the value in the CONNECT Packet used. The server uses this property to inform the Client that it is using a value other than that sent by the Client in the CONNACK. Refer to section 3.1.2.11.2 for a description of the use of Session Expiry Interval.

 

I believe this should instead read:

If the Session Expiry Interval is absent the value in the CONNECT Packet used. The server uses this property to inform the Client that it is using a value other than that sent by the Client in the CONNECT. Refer to section 3.1.2.11.2 for a description of the use of Session Expiry Interval.