In trying to replicate this, I found a problem with the pypilot signalk connection, which I added as an issue in the pypilot github. This might have been related to the failure to use the native signalk connection, although then I would have expected this to appear in your logging.
So for the time being, the use of sk-to-nmea0183, as I described earlier, might be the only viable option.
So for the time being, the use of sk-to-nmea0183, as I described earlier, might be the only viable option.