Thank you very much for your prompt response and clarification.
I can confirm that everything is working now.
I was slightly confused with the instructions on the Bluetooth plugin page that says
‚Important: When using Squeezelite with Bluetooth Speakers remove ‚-C 5‘ Parameter from Commandline Options and add ‚-B‘ to sychronize Squeezelite with the Bluetooth Speaker connection (On/Off).‘
I took this to mean leave the rest of the options that appeared on the command line options, not understanding that I should remove everything but I understand now.
I discovered it was my error – not all the packages had updated when I initialised the card!
I went through step-by-step today and ensured everything was OK. For some reason the update was hanging on the apache2 update so had to use putty to SSH in and complete the installation.