When you have this problem, does the route still look normal and you just have reduced miles, or does it delete entire sections out of the map as well?

I had a buddy that had this issue, he'd go 50 miles, get home and strava would say he went 45. This happened to him a few times, each time he emailed strava and they corrected the issue. I don't believe they knew what was causing it. They tried to blame the wahoo fitness app. The problem has went away now with recent updates to strava.