There are two known issues that may affect your rides: UTC Conversion and Strava Webhooks temporarily not functioning. These are both technical issues that most will not care to understand.
1. If your ride shows up in the NBC on the next day, the issue is UTC time conversion. When you log your ride in Strava, the time of the ride gets converted to UTC (Coordinated Universal Time). If you record your ride late in the day, the time gets converted and may push the date into the next day. This could cause an issue with streaks and losing the 20 point daily bonus. The developers are working to solve this issue. In the meantime, a work around approved by higher powers if a gap shows on your calendar, manually enter a ride in Strava of 1 mile on the desired day at 12:00 noon.
2. If your ride does not appear on the day you expect nor the next day, the issue is Strava Webhooks temporarily not functioning. Strava sends your ride to the NBC site almost immediately after you post it, UNLESS Strava Webhooks (the transfer mechanism) is temporally down. To solve this problem, the NBC runs a cleanup script over the weekend to catch up on these rides. Approved work around is to manually add a ride in Strava on the desired day.
3. Once a ride reaches the NBC site, editing the ride in Strava has no effect, including deletion of the ride in Strava. The developers are are working to solve this issue.