I got a "New FTP" message on the watch after a ride today.
As I have experienced a number of times before, the new data point didn't show on either GCM or Connect web, e.g. on Performance Stats-FTP.
After a discussion with support they told me everything was working as expected and cut off the chat. What I gleaned from Support is that they seem to be very focused on W/kg and not in the least bit interested in pure Wattage. The watch however seems very focused on Watts. The new FTP message states the new wattage not a new W/kg. It does however show W/kg in the "Performance" glance but with the actual wattage in a smaller font underneath. Support didn't seem to grasp the problem and told me that the reason I wasn't seeing an update was because the W/kg value hadn't changed significantly enough and they told me that it only took 0.01W/kg change for an update to show on the report.
Based on my suspicion about weight being an issue, which support weren't interested in, after Garmin ended the chat I did a weigh-in and sure enough the new data point from today's ride appeared in the report on Connect and on GCM.
So what manifested itself as a synchronisation problem is actually the fact that the watch is content to use an old weight value to display FTP whereas GCM and Connect are not, and neither an FTP in W nor W/kg will display in GCM or Connect if the last weigh-in is not recent enough.
I expected the data point to at least appear in the report or on the Performance Stats-FTP page when Watts rather than Watts/kg is selected in the report regardless of how recent the last weight-in occurred, however that is not the case. I'm not sure how recent the weigh-in has to be to display an FTP in GCM but I hadn't entered a weight for a few months.
If you're as confused as I was then hopefully this will resolve it for you. Support was most unhelpful. The reason they gave me as to why the update didn't show was completely false and demonstrated a significant lack of understanding of how FTP is reported.
On the Health Stats->Weight page there is a constant reminder to buy an Index S2 Smart Scale. Maybe I should have taken the hint.
