On my main computer (Windows 10), my BOINC manager has stalled with these messages:
31/05/2020 18:49:36 | | Project communication failed: attempting access to reference site
31/05/2020 18:49:38 | | Internet access OK - project servers may be temporarily down.
31/05/2020 18:51:22 | | Project communication failed: attempting access to reference site
31/05/2020 18:51:23 | | Internet access OK - project servers may be temporarily down.
This is after I suspended all tasks, rebooted, then resumed all tasks in case problem was at my end.
The multiple Raspberry Pis running on stand-alone configuration appear to be working fine and fetching new work. Screenshot of tasks show all trying to upload.