Version 2.0.5 breaks connection to MQTT broker using pubsubclient version 2.8 - Err -2

[PaulM47]

I've just tried to update an arduino nano V3, last updated in June, that connects to a Raspberry Pi Mosquitto MQTT broker using 'pubsubclient' and 'ethernetenc' libraries. With the latest 'ethernetenc' library (2.0.5) I just see MQTT Err 2 messages and no connection, 'pubsubclient' is version 2.8. I backed up to 'ethernetenc' version 2.0.4 and all is working again. I'm not a programmer, just an enthusiastic DIYer, there's nothing special in my code (happy to supply a copy if required), just cobbled together from examples on the web, so have no idea how to track down the problem, sorry.

Hardware is Arduino Nano V3 and ENC28J60 boards from AZ Delivery.

PaulM