The only times I deal with 'neutral' starts where it's not a race from the get go is when they are listed/categorized as group rides. These are generally rides where everyone rides together for 3 laps, maybe doing drills, intermediate sprints but generally together. Then with 1 lap to go or at a designated start point everyone must be behind the ride leader and the ride leader will give the signal to race if you choose. Some do, others will just continue on with the group. Anyone not behind the leader at the 'neutral start' is excluded from the so called standings after the fact.