HRSS support is live now and is the default for non-cycling activities. For cycling the default is still “time in HR zones” with fallback to HRSS if there isn’t enough data or the model is poor. The “time in HR zones” model gives better results (for me, for cycling) than HRSS.
I am going to deploy code tonight to fix up everyones data. Right now if you have an iffy activity you want to fix, click “Reset” under the ride timeline chart.