Google Maps Api V3 says :
MAX_WAYPOINTS_EXCEEDED indicates that too many DirectionsWaypoints were provided in the DirectionsRequest. The maximum allowable waypoints are 8, plus the source and destination. The Google Premier Maps API clients have 23 waypoints, as well as a source and destination.
You can go for the Premier API, but I think it will cost you around $ 10,000 a year
Flov
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