You need approval for certain paint schemes. There is a rule somewhere too about how only a certain percentage of the aircraft can be coloured beyond that of the factory specification, eg 10%.
There have been many occasions when aircraft / operators have been penalised for too much colour on their aircraft but you usually only hear this offence tacked on behind a string of others.
Unless you can provide a reference, I'm calling Bovine Scatology on that one.