You can crop your recordings at the start as long as you know the exact place you want the start and finish
No, I didn't but will try it.
With the outage Strava had last year and clearly no guarantee of it not happening again best if any ride is uploaded elsewhere as well, Garmins should also load to Garmin Connect and there is the likes of Komoot as well which any device should be also uploading to. In the event of a Strava failure there is then the subseqy option of importing the GPX file having downloaded it from where the ride has been saved.