As per subject line, DSWs are sometimes all stated as ‘rest day’ on my Forerunner 265 running 17.26. I have seen this twice, once where my current day and all further days were ‘Rest Day’, and once where the current day said ‘run completed’ (I had not completed workout). In the first instance I was able to fix by changing my long workout days, on the 2nd instance, the watch still insisted I had completed my workout on that day and my next 2 days were rest days.
Tried multiple resets of watch, and opening and closing of Connect App but as above only sort of workaround was by changing long workout days.
I have seen this issue reported in multiple instances elsewhere.
If I can assist further in your investigation please let me know.