2022-06-06, 09:57 AM
I had a very similar problem with an NMEA 0183 source, so I don't think it's specific to SeaTalk.
With a Garmin chartplotter sending RMB, RMC, APB and BWC messages, all the messages had the correct timestamp except BWC which was consistently 4 weeks and 1 hour earlier :
With a Garmin chartplotter sending RMB, RMC, APB and BWC messages, all the messages had the correct timestamp except BWC which was consistently 4 weeks and 1 hour earlier :