I'm definitely experiencing a problem with heart rate that did not occur in any of the previous firmwares so I must assume it is a new bug. Not sure if it's on the f7 or 1030+ side.
What happens:
I activate heart rate transmission on my f7 solor and verify that my 1030+ receives it.
Start cycling and after 40 to 50 minutes into the workout the watch stops registering my heart rate properly. Usually it drops to about 80 and won't go above 115 anymore, whereas my heart rate is around at least 140. Verified this with my wife's Venue which track my heart rate perfectly fine.
FW f7 solar: 9.37
FW 1030+: 6.50
This never happened with previous f firmware so getting a chest sensor is not the solution, this must be a bug as during all other activities my heart rate tracks just fine.
And yes, I did a few hard and soft resets. I've tried to post a bug report to Garmin Support but that must be a joke, the submit button doesn't work in typical Garmin fashion.