Complaints about BYD (1211) over its move to offer free smart driving features across most of its line-up have flooded a prominent Chinese auto quality platform, many from customers who said they had overpaid for their cars.

Over 4,700 complaints were filed against BYD cars between February 11-17 on 12365auto.com, a third-party auto consumer complaints platform, compared with about 150 the week before and roughly 500 for January.

BYD cars, including ones from its best-selling Ocean and Dynasty series, also took the top 10 spots on a list the platform publishes that ranks models by the number of complaints received.

One complaint, sent in by an owner of a Seal 06 DM-i plug-in hybrid sedan, said they had repeatedly asked the salesperson when buying the car if a newer model would be launched this year.