Whenever my F6 Pro reboots all saved activities on the watch change from miles to a combination of yards and kilometers. Through trial and error I have found calibrating the altimeter corrects the problem until next reboot.
After updating to v6.00 this morning, I reset to default settings hoping that would solve the problem but it has not. Garmin support has been very good about working with me but as of yet, has not been able to re-create or fix the issue. I figured I’d just put this out here to see if anyone has experienced the same or may have any insights. Thanks.