UPDATE: It looks like this issue was simply due to not being able to see the ‘Active Filters’ list from within the dashboard (which was due to running an older version of the plugin, which was in turn due to having trouble updating our license keys). Once we were able to update our license keys and then update the plugins, the ‘Active Filters’ issue was resolved and we were then able to customize the filter title to include the £ sign as needed.
So this thread can be closed as everything is all set now.
Thank you!