Thanks. I have taken a look and I think your Stages power sensor was the cause. It seems to have been constantly reconnecting for some reason, and it looks like that eventually prevented the app from handling the GPS updates. I have never seen anything like it.
The sensor connected 3782 times (instead of the usual once). If you go to the Power tab and change Power to Log then you will see 18000+ log messages about it. This has never happened in all the months of sensor testing, but I never heard of anyone testing with that sensor. Sorry about that. Unfortunately it is impossible to test every make and model of sensor. I recommend not using that sensor until I can look into a fix.
thanks - I was going to report a suspected similar issue with my foot pod - as I could see the 'pace' field alternating between a valid figure and null (empty) with rapidly changing status messages at the bottom of the display when paused (too quick to read, but perhaps something about sensors connecting).
checking the log entry for that run I can see multiple entries for 'Initialising sensor connections' after which the pod is found and then connected over and over - same issue, different sensor.
on the ride the stages crank was connected via ANT to the wahoo unit, with no apparent issues - I've recorded various rides in ismoothrun with a similar arrangement, but WOD is my preferred app ;-) (also with zwift on apple tv - so I don't think the stages unit has any issues with BLE & ANT simultaneously).
I've removed the pairing, power cycled the watch, re-paired and done a short test with the foot pod - showing no issues and a consistent pace data field... seems like a watchOS oddity, although I'd not seen this with ismoothrun previously... but the constant re-connection is probably what caused my previous query about the watch being unresponsive with wrist gestures etc. if it's very busy re-establishing sensor connections ?
at least I know about the log viewer to check again on some more test rides / runs... you did mention you had some updates in the pipeline for the new sensor functionality - hopefully this might address the issue ?